5-(n-benzyl tetrahydroisoquinolin-6-yl) pyridin-3-yl acetic acid derivatives as inhibitors of human immunodeficiency virus replication

ABSTRACT

Disclosed are compounds of Formula I, including pharmaceutically acceptable salts, pharmaceutical compositions comprising the compounds, methods for making the compounds and their use in inhibiting HIV integrase and treating those infected with HIV or AIDS.

CROSS REFERENCE TO RELATED INVENTION

This application claims the benefit of U.S. provisional application Ser.No. 62/203,791 filed Aug. 11, 2015.

FIELD OF THE INVENTION

The invention relates to compounds, compositions, and methods for thetreatment of human immunodeficiency virus (HIV) infection. Moreparticularly, the invention provides novel inhibitors of HIV,pharmaceutical compositions containing such compounds, and methods forusing these compounds in the treatment of HIV infection. The inventionalso relates to methods for making the compounds hereinafter described.

BACKGROUND OF THE INVENTION

Human immunodeficiency virus (HIV) has been identified as theetiological agent responsible for acquired immune deficiency syndrome(AIDS), a fatal disease characterized by destruction of the immunesystem and the inability to fight off life threatening opportunisticinfections. Recent statistics indicate that an estimated 35.3 millionpeople worldwide are infected with the virus (UNAIDS: Report on theGlobal HIV/AIDS Epidemic, 2013). In addition to the large number ofindividuals already infected, the virus continues to spread. Estimatesfrom 2013 point to close to 3.4 million new infections in that yearalone. In the same year there were approximately 1.6 million deathsassociated with HIV and AIDS.

Current therapy for HIV-infected individuals consists of a combinationof approved anti-retroviral agents. Over two dozen drugs are currentlyapproved for HIV infection, either as single agents or as fixed dosecombinations or single tablet regimens, the latter two containing 2-4approved agents. These agents belong to a number of different classes,targeting either a viral enzyme or the function of a viral proteinduring the virus replication cycle. Thus, agents are classified aseither nucleotide reverse transcriptase inhibitors (NRTIs),non-nucleotide reverse transcriptase inhibitors (NNRTIs), proteaseinhibitors (PIs), integrase inhibitors (INIs), or entry inhibitors (one,maraviroc, targets the host CCR5 protein, while the other, enfuvirtide,is a peptide that targets the gp41 region of the viral gp160 protein).In addition, a pharmacokinetic enhancer with no antiviral activity,i.e., cobicistat, available from Gilead Sciences, Inc. under thetradename TYBOST™ (cobicistat) tablets, has recently been approved foruse in combinations with certain antiretroviral agents (ARVs) that maybenefit from boosting.

In the US, where combination therapy is widely available, the number ofHIV-related deaths has dramatically declined (Palella, F. J.; Delany, K.M.; Moorman, A. C.; Loveless, M. O.; Further, J.; Satten, G. A.;Aschman, D. J.; Holmberg, S. D. N. Engl. J. Med. 1998, 338, 853-860).

Unfortunately, not all patients are responsive and a large number failthis therapy. In fact, initial studies suggest that approximately 30-50%of patients ultimately fail at least one drug in the suppressivecombination. Treatment failure in most cases is caused by the emergenceof viral resistance. Viral resistance in turn is caused by thereplication rate of HIV-1 during the course of infection combined withthe relatively high viral mutation rate associated with the viralpolymerase and the lack of adherence of HIV-infected individuals intaking their prescribed medications. Clearly, there is a need for newantiviral agents, preferably with activity against viruses alreadyresistant to currently approved drugs. Other important factors includeimproved safety and a more convenient dosing regimen than many of thecurrently approved drugs.

Compounds which inhibit HIV replication have been disclosed. See, forexample, the following patent applications: WO2007131350, WO2009062285,WO2009062288, WO2009062289, WO2009062308, WO2010130034, WO2010130842,WO2011015641, WO2011076765, WO2012033735, WO2013123148, WO2013134113,WO2014164467, WO2014159959, and WO2015126726.

What is now needed in the art are additional compounds which are noveland useful in the treatment of HIV. Additionally, these compounds maydesirably provide advantages for pharmaceutical uses, for example, withregard to one or more of their mechanisms of action, binding, inhibitionefficacy, target selectivity, solubility, safety profiles, orbioavailability. Also needed are new formulations and methods oftreatment which utilize these compounds.

SUMMARY OF THE INVENTION

The invention encompasses compounds of Formula I, includingpharmaceutically acceptable salts thereof, as well as pharmaceuticalcompositions, and their use in inhibiting HIV and treating thoseinfected with HIV or AIDS.

By virtue of the present invention, it is now possible to providecompounds that are novel and are useful in the treatment of HIV.Additionally, the compounds may provide advantages for pharmaceuticaluses, for example, with regard to one or more of their mechanism ofaction, binding, inhibition efficacy, target selectivity, solubility,safety profiles, or bioavailability.

The invention also provides pharmaceutical compositions comprising thecompounds of the invention, including pharmaceutically acceptable saltsthereof, and a pharmaceutically acceptable carrier, excipient, and/ordiluent.

In addition, the invention provides methods of treating HIV infectioncomprising administering a therapeutically effective amount of thecompounds of the invention to a patient.

In addition, the invention provides methods for inhibiting HIVintegrase.

Also provided in accordance with the invention are methods for makingthe compounds of the invention.

The present invention is directed to these, as well as other importantends, hereinafter described.

DESCRIPTION OF THE INVENTION

Unless specified otherwise, these terms have the following meanings.

“Alkyl” means a straight or branched saturated hydrocarbon comprised of1 to 10 carbons, and preferably 1 to 6 carbons.

“Alkenyl” means a straight or branched alkyl group comprised of 2 to 10carbons with at least one double bond and optionally substituted with0-3 halo or alkoxy group.

“Alkynyl” means a straight or branched alkyl group comprised of 2 to 10carbons, preferably 2 to 6 carbons, containing at least one triple bondand optionally substituted with 0-3 halo or alkoxy group.

“Aryl” mean a carbocyclic group comprised of 1-3 rings that are fusedand/or bonded and at least one or a combination of which is aromatic.The non-aromatic carbocyclic portion, where present, will be comprisedof C₃ to C₇ alkyl group. Examples of aromatic groups include, but arenot limited to indanyl, indenyl, naphthyl, phenyl, tetrahydronaphthyland cyclopropylphenyl. The aryl group can be attached to the parentstructure through any substitutable carbon atom in the group.

“Arylalkyl” is a C₁-C₅ alkyl group attached to 1 to 2 aryl groups andlinked to the parent structure through the alkyl moiety. Examplesinclude, but are not limited to, —(CH₂)_(n)Ph with n=1-5, —CH(CH₃)Ph,—CH(Ph)2.

“Aryloxy” is an aryl group attached to the parent structure by oxygen.

“Cycloalkyl” means a monocyclic ring system composed of 3 to 7 carbons.

“Halo” includes fluoro, chloro, bromo, and iodo.

“Haloalkyl” and “haloalkoxy” include all halogenated isomers frommonohalo to perhalo.

“Heteroaryl” is a subset of heterocyclic group as defined below and iscomprised of 1-3 rings where at least one or a combination of which isaromatic and that the aromatic group contains at least one atom chosenfrom a group of oxygen, nitrogen or sulfur.

“Heterocyclyl or heterocyclic” means a cyclic group of 1-3 ringscomprised of carbon and at least one other atom selected independentlyfrom oxygen, nitrogen and sulfur. The rings could be bridged, fusedand/or bonded, through a direct or spiro attachment, with the option tohave one or a combination thereof be aromatic. Examples include, but arenot limited to, azaindole, azaindoline, azetidine, benzimidazole,bezodioxolyl, benzoisothiazole, benzothiazole, benzothiadiazole,benzothiophene, benzoxazole, carbazole, chroman, dihalobezodioxolyl,dihydrobenzofuran, dihydrobenzo[1,4]oxazine,1,3-dihydrobenzo[c]thiophene 2,2-dioxide, 2,3-dihydrobenzo[d]isothiazole1,1-dioxide, 3,4-dihydro-2H-pyrido[3,2-b][1,4]oxazine,2,3-dihydro-H-pyrrolo[3,4-c]pyridine and its regioisomeric variants,6,7-dihydro-5H-pyrrolo[2,3-b]pyrazine and its regioisomeric variants,furanylphenyl, imidazole, imidazo[1,2-a]pyridine, indazole, indole,indoline, isoquinoline, isoquinolinone, isothiazolidine 1,1-dioxide,morpholine, 2-oxa-5-azabicyclo[2.2.1]heptane, oxadiazole-phenyl,oxazole, phenylaztidine, phenylindazole, phenylpiperidine,phenylpiperizine, phenyloxazole, phenylpyrrolidine, piperidine,pyridine, pyridinylphenyl, pyridinylpyrrolidine, pyrimidine,pyrimidinylphenyl, pyrrazole-phenyl, pyrrolidine, pyrrolidin-2-one,1H-pyrazolo[4,3-c]pyridine and its regioisomeric variants, pyrrole,5H-pyrrolo[2,3-b]pyrazine, 7H-pyrrolo[2,3-d]pyrimidine and itsregioisomeric variants, quinazoline, quinoline, quinoxaline,tetrahydroisoquinoline, 1,2,3,4-tetrahydro-1,8-naphthyridine,tetrahydroquinoline, 4,5,6,7-tetrahydrothieno[3,2-c]pyridine,1,2,5-thiadiazolidine 1,1-dioxide, thiophene, thiophenylphenyl,triazole, or triazolone. Unless otherwise specifically set forth, theheterocyclic group can be attached to the parent structure through anysuitable atom in the group that results in a stable compound.

It is understood that a subset of the noted heterocyclic examplesencompass regioisomers. For instance, “azaindole” refers to any of thefollowing regioisomers: 1H-pyrrolo[2,3-b]pyridine,1H-pyrrolo[2,3-c]pyridine, 1H-pyrrolo[3,2-c]pyridine, and1H-pyrrolo[3,2-b]pyridine. In addition the “regioisomer variants”notation as in, for example, “5H-pyrrolo[2,3-b]pyrazine and itsregioisomeric variants” would also encompass7H-pyrrolo[2,3-d]pyrimidine, 7H-pyrrolo[2,3-c]pyridazine,1H-pyrrolo[2,3-d]pyridazine, 5H-pyrrolo[3,2-c]pyridazine, and5H-pyrrolo[3,2-d]pyrimidine. Similarly,6,7-dihydro-5H-pyrrolo[2,3-b]pyrazine and its regioisomeric variantswould encompass 6,7-dihydro-5H-pyrrolo[2,3-d]pyrimidine and6,7-dihydro-5H-pyrrolo[2,3-c]pyridazine. It is also understood that thelack of “regioisomeric variants” notation does not in any way restrictthe claim scope to the noted example only.

“Heterocyclylalkyl” is a heterocyclyl moiety attached to the parentstructure through C₁-C₅ alkyl group. Examples include, but are notlimited to, —(CH₂)_(n)—R or —CH(CH₃)—(R^(Z)) where n=1-5 and that R^(Z)is chosen from benzimidazole, imidazole, indazole, isooxazole,phenyl-pyrazole, pyridine, quinoline, thiazole, triazole, triazolone,oxadiazole.

Terms with a hydrocarbon moiety (e.g. alkoxy) include straight andbranched isomers for the hydrocarbon portion with the indicated numberof carbon atoms.

Bonding and positional bonding relationships are those that are stableas understood by practitioners of organic chemistry.

Parenthetic and multiparenthetic terms are intended to clarify bondingrelationships to those skilled in the art. For example, a term such as((R)alkyl) means an alkyl substituent further substituted with thesubstituent R.

Substituents which are illustrated by chemical drawing to bond atvariable positions on a multiple ring system (for example a bicyclicring system) are intended to bond to the ring where they are drawn toappend. Parenthetic and multiparenthetic terms are intended to clarifybonding relationships to those skilled in the art. For example, a termsuch as ((R)alkyl) means an alkyl substituent further substituted withthe substituent R.

“Combination,” “coadministration,” “concurrent” and similar termsreferring to the administration of a compound of Formula I with at leastone anti-HIV agent mean that the components are part of a combinationantiretroviral therapy or highly active antiretroviral therapy (“HAART”)as understood by practitioners in the field of AIDS and HIV infection.

“Therapeutically effective” means the amount of agent required toprovide a benefit to a patient as understood by practitioners in thefield of AIDS and HIV infection. In general, the goals of treatment aresuppression of viral load, restoration and preservation of immunologicfunction, improved quality of life, and reduction of HIV-relatedmorbidity and mortality.

“Patient” means a person infected with the HIV virus.

“Treatment,” “therapy,” “regimen,” “HIV infection,” “ARC,” “AIDS” andrelated terms are used as understood by practitioners in the field ofAIDS and HIV infection.

Those terms not specifically set forth herein shall have the meaningwhich is commonly understood and accepted in the art.

The invention includes all pharmaceutically acceptable salt forms of thecompounds. Pharmaceutically acceptable salts are those in which thecounter ions do not contribute significantly to the physiologicalactivity or toxicity of the compounds and as such function aspharmacological equivalents. These salts can be made according to commonorganic techniques employing commercially available reagents. Someanionic salt forms include acetate, acistrate, besylate, bromide,chloride, citrate, fumarate, glucouronate, hydrobromide, hydrochloride,hydroiodide, iodide, lactate, maleate, mesylate, nitrate, pamoate,phosphate, succinate, sulfate, tartrate, tosylate, and xinofoate. Somecationic salt forms include ammonium, aluminum, benzathine, bismuth,calcium, choline, diethylamine, diethanolamine, lithium, magnesium,meglumine, 4-phenylcyclohexylamine, piperazine, potassium, sodium,tromethamine, and zinc.

Some of the compounds of the invention exist in stereoisomeric forms.The invention includes all stereoisomeric forms of the compoundsincluding enantiomers and diastereromers. Methods of making andseparating stereoisomers are known in the art. The invention includesall tautomeric forms of the compounds. The invention includesatropisomers and rotational isomers.

The invention is intended to include all isotopes of atoms occurring inthe present compounds. Isotopes include those atoms having the sameatomic number but different mass numbers. By way of general example andwithout limitation, isotopes of hydrogen include deuterium and tritium.Isotopes of carbon include ¹³C and ¹⁴C. Isotopically-labeled compoundsof the invention can generally be prepared by conventional techniquesknown to those skilled in the art or by processes analogous to thosedescribed herein, using an appropriate isotopically-labeled reagent inplace of the non-labeled reagent otherwise employed. Such compounds mayhave a variety of potential uses, for example as standards and reagentsin determining biological activity. In the case of stable isotopes, suchcompounds may have the potential to favorably modify biological,pharmacological, or pharmacokinetic properties.

In an aspect of the invention, there is provided a compound of FormulaI:

wherein:R¹ is selected from hydrogen, alkyl, or cycloalkyl;R² is selected from tetrahydroisoquinolinyl and is substituted with 1 R⁶substituent and also with 0-3 halo or alkyl substituents;R³ is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl,morpholinyl, homopiperidinyl, homopiperazinyl, or homomorpholinyl, andis substituted with 0-3 substituents selected from cyano, halo, alkyl,haloalkyl, alkoxy, and haloalkoxy;R⁴ is selected from alkyl or haloalkyl;R⁵ is alkyl;R⁶ is selected from Ar¹, (Ar¹)alkyl, (chromanyl)alkyl, cyanocycloalkylor (dihydrobenzodioxinyl)alkyl; andAr¹ is phenyl substituted with 0-5 substituents selected from cyano,halo, alkyl, cycloalkyl, haloalkyl, hydroxy, alkoxy, haloalkoxy,(hydroxy)alkoxy, (alkoxy)alkoxy, phenoxy, benzyloxy, carboxy, phenyl,and cyanocycloalkyl;or a pharmaceutically acceptable salt thereof.

In an aspect of the invention, R² is tetrahydroisoquinolinyl substitutedwith 1 R⁶ substituent.

In an aspect of the invention, R³ is piperidinyl substituted with 0-3substituents selected from cyano, halo, alkyl, haloalkyl, alkoxy, andhaloalkoxy.

In an aspect of the invention, R⁶ is (Ar¹)alkyl.

In an aspect of the invention, R⁶ is Ar¹, (chromanyl)alkyl,(dihydrobenzodioxinyl)alkyl, or cyanocycloalkyl.

In an aspect of the invention, Ar¹ is phenyl substituted with 0-3substituents selected from cyano, halo, alkyl, cycloalkyl, haloalkyl,hydroxy, alkoxy, haloalkoxy, (hydroxy)alkoxy, (alkoxy)alkoxy, phenoxy,benzyloxy, carboxy, phenyl, and cyanocycloalkyl.

In an aspect of the invention, there is provided a compound of FormulaI:

wherein:R¹ is selected from hydrogen, alkyl, or cycloalkyl;R² is selected from tetrahydroisoquinolinyl and is substituted with 1 R⁶substituent and also with 0-3 halo or alkyl substituents;R³ is piperidinyl substituted with 0-3 substituents selected from cyano,halo, alkyl, haloalkyl, alkoxy, and haloalkoxy;R⁴ is selected from alkyl or haloalkyl;R⁵ is alkyl;R⁶ is selected from Ar¹, (Ar¹)alkyl, (chromanyl)alkyl, cyanocycloalkylor (dihydrobenzodioxinyl)alkyl; andAr¹ is phenyl substituted with 0-5 substituents selected from cyano,halo, alkyl, cycloalkyl, haloalkyl, hydroxy, alkoxy, haloalkoxy,(hydroxy)alkoxy, (alkoxy)alkoxy, phenoxy, benzyloxy, carboxy, phenyl,and cyanocycloalkyl;or a pharmaceutically acceptable salt thereof.

In an aspect of the invention, there is provided a compound of FormulaI:

wherein:R¹ is selected from hydrogen, alkyl, or cycloalkyl;R² is selected from tetrahydroisoquinolinyl and is substituted with 1 R⁶substituent and also with 0-3 halo or alkyl substituents;R³ is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl,morpholinyl, homopiperidinyl, homopiperazinyl, or homomorpholinyl, andis substituted with 0-3 substituents selected from cyano, halo, alkyl,haloalkyl, alkoxy, and haloalkoxy;R⁴ is selected from alkyl or haloalkyl;R⁵ is alkyl;R⁶ is (Ar¹)alkyl; andAr¹ is phenyl substituted with 0-5 substituents selected from cyano,halo, alkyl, cycloalkyl, haloalkyl, hydroxy, alkoxy, haloalkoxy,(hydroxy)alkoxy, (alkoxy)alkoxy, phenoxy, benzyloxy, carboxy, phenyl,and cyanocycloalkyl;or a pharmaceutically acceptable salt thereof.

In an aspect of the invention, there is provided a compound of FormulaI:

wherein:R¹ is selected from hydrogen, alkyl, or cycloalkyl;R² is selected from tetrahydroisoquinolinyl and is substituted with 1 R⁶substituent and also with 0-3 halo or alkyl substituents;R³ is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl,morpholinyl, homopiperidinyl, homopiperazinyl, or homomorpholinyl, andis substituted with 0-3 substituents selected from cyano, halo, alkyl,haloalkyl, alkoxy, and haloalkoxy;R⁴ is selected from alkyl or haloalkyl;R⁵ is alkyl;R⁶ is selected from Ar¹, (chromanyl)alkyl, (dihydrobenzodioxinyl)alkyl,or cyanocycloalkyl; andAr¹ is phenyl substituted with 0-5 substituents selected from cyano,halo, alkyl, cycloalkyl, haloalkyl, hydroxy, alkoxy, haloalkoxy,(hydroxy)alkoxy, (alkoxy)alkoxy, phenoxy, benzyloxy, carboxy, phenyl,and cyanocycloalkyl;or a pharmaceutically acceptable salt thereof.

In an aspect of the invention, there is provided a compound of FormulaI:

wherein:R¹ is selected from hydrogen, alkyl, or cycloalkyl;R² is selected from tetrahydroisoquinolinyl and is substituted with 1 R⁶substituent and also with 0-3 halo or alkyl substituents;R³ is selected from azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl,morpholinyl, homopiperidinyl, homopiperazinyl, or homomorpholinyl, andis substituted with 0-3 substituents selected from cyano, halo, alkyl,haloalkyl, alkoxy, and haloalkoxy;R⁴ is selected from alkyl or haloalkyl;R⁵ is alkyl;R⁶ is selected from Ar¹, (Ar¹)alkyl, (chromanyl)alkyl, cyanocycloalkylor (dihydrobenzodioxinyl)alkyl; andAr¹ is phenyl substituted with 0-3 substituents selected from cyano,halo, alkyl, cycloalkyl, haloalkyl, hydroxy, alkoxy, haloalkoxy,(hydroxy)alkoxy, (alkoxy)alkoxy, phenoxy, benzyloxy, carboxy, phenyl,and cyanocycloalkyl;or a pharmaceutically acceptable salt thereof.

For a particular compound of Formula I, the scope of any instance of avariable substituent, including R¹, R², R³, R⁴, R⁵, R⁶ and Ar¹ can beused independently with the scope of any other instance of a variablesubstituent. As such, the invention includes combinations of thedifferent aspects.

In an aspect of the invention, there is provided a composition usefulfor treating HIV infection comprising a therapeutic amount of a compoundof Formula I and a pharmaceutically acceptable carrier. In an aspect ofthe invention, the composition further comprises a therapeuticallyeffective amount at least one other agent used for treatment of AIDS orHIV infection selected from nucleoside HIV reverse transcriptaseinhibitors, non-nucleoside HIV reverse transcriptase inhibitors, HIVprotease inhibitors, HIV fusion inhibitors, HIV attachment inhibitors,CCR5 inhibitors, CXCR4 inhibitors, HIV budding or maturation inhibitors,and HIV integrase inhibitors, and a pharmaceutically acceptable carrier.In an aspect of the invention, the other agent is dolutegravir.

In an aspect of the invention, there is provided a method for treatingHIV infection comprising administering a therapeutically effectiveamount of a compound of Formula I, or a pharmaceutically acceptable saltthereof, to a patient in need thereof. In an aspect of the invention,the method further comprises administering a therapeutically effectiveamount of at least one other agent used for treatment of AIDS or HIVinfection selected from nucleoside HIV reverse transcriptase inhibitors,non-nucleoside HIV reverse transcriptase inhibitors, HIV proteaseinhibitors, HIV fusion inhibitors, HIV attachment inhibitors, CCR5inhibitors, CXCR4 inhibitors, HIV budding or maturation inhibitors, andHIV integrase inhibitors. In an aspect of the invention, the other agentis dolutegravir.

In an aspect of the invention, the other agent is administered to thepatient prior to, simultaneously with, or subsequently to the compoundof Formula I.

Preferred compounds in accordance with the present invention include thefollowing:

-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-3-((6-(5-(tert-butoxy(carboxy)methyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-3,4-dihydroisoquinolin-2(1H)-yl)methyl)benzoic    acid;-   (S)-2-(5-(2-([1,1′-biphenyl]-3-ylmethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (2S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(1-phenylethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(5-(2-([1,1′-biphenyl]-4-ylmethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-methyl-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-methyl-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,4-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,3-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-3-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,5-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-(tert-butyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,5-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,5-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,6-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3,4,5-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-4-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-isopropylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,4-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,5-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid-   (S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,3-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,3,4-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(5-chloro-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-5-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,3,6-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-5-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-5-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-fluoro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluoro-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,4,5-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-methyl-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-chlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-chlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,4,6-trimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,4,6-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-isopropylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-ethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-cyanobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-cyanobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(5-cyano-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-cyanobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-cyano-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-fluoro-2-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2,3-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,3-difluoro-4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-5-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3,5-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,4-difluoro-5-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-isopropylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,4,5-trimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,5-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1l-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,3-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-(tert-butyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,5-difluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(5-(2-(2-(benzyloxy)-3,5-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4,5-difluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,3-difluoro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-(2-hydroxyethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluoro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-dichloro-6-ethoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,3-dichloro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluoro-3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1l-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-2-fluoro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluoro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,5-difluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,3,5-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-methoxy-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(5-chloro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-ethoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-(difluoromethoxy)-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluoro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-4-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-methoxy-4-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-5-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-methoxy-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-5-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-(difluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-(difluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-methoxy-5-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-(1,1,2,2-tetrafluoroethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-fluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-(1,1,2,2-tetrafluoroethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-ethoxy-2,4-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,4-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,6-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(5-chloro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-2,6-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-6-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-isopropyl-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-methoxy-4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-methoxy-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-isopropyl-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluoro-6-hydroxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-methoxy-2,3-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-methoxy-2,5-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-ethoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-isopropoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-methoxy-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-isopropoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-isobutoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-isopropoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(chroman-6-ylmethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-((2,3-dihydrobenzo[b][1,4]dioxin-6-yl)methyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(5-(2-(3,4-bis(difluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-((2,3-dihydrobenzo[b][1,4]dioxin-5-yl)methyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-phenoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-isopropoxy-2,6-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,4-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(4-(1-cyanocyclopropyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-(nonyloxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-Butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2-methylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-Butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2-methyl-5-(2-(2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-Butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3,4-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2,3-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid;-   (S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-fluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic    acid; and-   (S)-2-(tert-Butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2-methylpyridin-3-yl)acetic    acid; and-   pharmaceutically acceptable salts thereof.

The compounds of the invention herein described may typically beadministered as pharmaceutical compositions. These compositions arecomprised of a therapeutically effective amount of a compound of FormulaI or its pharmaceutically acceptable salt, and a pharmaceuticallyacceptable carrier and may contain conventional excipients and/ordiluents. A therapeutically effective amount is that which is needed toprovide a meaningful patient benefit. Pharmaceutically acceptablecarriers are those conventionally known carriers having acceptablesafety profiles. Compositions encompass all common solid and liquidforms, including capsules, tablets, lozenges, and powders, as well asliquid suspensions, syrups, elixirs, and solutions. Compositions aremade using available formulation techniques, and excipients (such asbinding and wetting agents) and vehicles (such as water and alcohols)which are generally used for compositions. See, for example, Remington'sPharmaceutical Sciences, 17th edition, Mack Publishing Company, Easton,Pa. (1985).

Solid compositions which are normally formulated in dosage units andcompositions providing from about 1 to 1000 milligram (“mg”) of theactive ingredient per dose are typical. Some examples of dosages are 1mg, 10 mg, 100 mg, 250 mg, 500 mg, and 1000 mg. Generally, otherantiretroviral agents will be present in a unit range similar to agentsof that class used clinically. Typically, this is about 0.25-1000mg/unit.

Liquid compositions are usually in dosage unit ranges. Generally, theliquid composition will be in a unit dosage range of about 1-100milligram per milliliter (“mg/mL”). Some examples of dosages are 1mg/mL, 10 mg/mL, 25 mg/mL, 50 mg/mL, and 100 mg/mL. Generally, otherantiretroviral agents will be present in a unit range similar to agentsof that class used clinically. Typically, this is about 1-100 mg/mL.

The invention encompasses all conventional modes of administration; oraland parenteral methods are preferred. Generally, the dosing regimen willbe similar to other antiretroviral agents used clinically. Typically,the daily dose will be about 1-100 milligram per kilogram (“mg/kg”) bodyweight daily. Generally, more compound is required orally and lessparenterally. The specific dosing regimen, however, will be determinedby a physician using sound medical judgment.

The compounds of this invention desirably have activity against HIV.Accordingly, another aspect of the invention is a method for treatingHIV infection in a human patient comprising administering atherapeutically effective amount of a compound of Formula I, or apharmaceutically acceptable salt thereof, with a pharmaceuticallyacceptable carrier, excipient and/or diluent.

The invention also encompasses methods where the compound is given incombination therapy. That is, the compound can be used in conjunctionwith, but separately from, other agents useful in treating AIDS and HIVinfection. The compound can also be used in combination therapy whereinthe compound and one or more of the other agents are physically togetherin a fixed-dose combination (FDC). Some of these agents include HIVattachment inhibitors, CCR5 inhibitors, CXCR4 inhibitors, HIV cellfusion inhibitors, HIV integrase inhibitors, HIV nucleoside reversetranscriptase inhibitors, HIV non-nucleoside reverse transcriptaseinhibitors, HIV protease inhibitors, budding and maturation inhibitors,HIV capsid inhibitors, anti-infectives, and immunomodulators, such as,for example, PD-1 inhibitors, PD-L1 inhibitors, antibodies, and thelike. In these combination methods, the compound of Formula I willgenerally be given in a daily dose of about 1-100 mg/kg body weightdaily in conjunction with other agents. The other agents generally willbe given in the amounts used therapeutically. The specific dosingregimen, however, will be determined by a physician using sound medicaljudgment.

Examples of nucleoside HIV reverse transcriptase inhibitors includeabacavir, didanosine, emtricitabine, lamivudine, stavudine, tenofovir,zalcitabine, and zidovudine.

Examples of non-nucleoside HIV reverse transcriptase inhibitors includedelavirdine, efavirenz, etrivirine, nevirapine, and rilpivirine.

Examples of HIV protease inhibitors include amprenavir, atazanavir,darunavir, fosamprenavir, indinavir, lopinavir, nelfinavir, ritonavir,saquinavir and, tipranavir.

An example of an HIV fusion inhibitor is enfuvirtide or T-1249.

An example of an HIV entry inhibitor is maraviroc.

Examples of HIV integrase inhibitors include dolutegravir, elvitegravir,or raltegravir.

An example of an HIV attachment inhibitor is fostemsavir.

An example of an HIV maturation inhibitor is BMS-955176, having thefollowing structure:

Thus, as set forth above, contemplated herein are combinations of thecompounds of Formula I, together with one or more agents useful in thetreatment of AIDS. For example, the compounds of the invention may beeffectively administered, whether at periods of pre-exposure and/orpost-exposure, in combination with effective amounts of the AIDSantivirals, immunomodulators, anti-infectives, or vaccines, such asthose in the following non-limiting table:

Drug Name Manufacturer Indication ANTIVIRALS Rilpivirine Tibotec HIVinfection, AIDS, ARC (non-nucleoside reverse transcriptase inhibitor)COMPLERA ® Gilead HIV infection, AIDS, ARC; combination withemtricitabine, rilpivirine, and tenofovir disoproxil fumarate 097Hoechst/Bayer HIV infection, AIDS, ARC (non-nucleoside reversetranscriptase (RT) inhibitor) Amprenavir Glaxo Wellcome HIV infection,141 W94 AIDS, ARC GW 141 (protease inhibitor) Abacavir (1592U89) GlaxoWellcome HIV infection, GW 1592 AIDS, ARC (RT inhibitor) AcemannanCarrington Labs ARC (Irving, TX) Acyclovir Burroughs Wellcome HIVinfection, AIDS, ARC AD-439 Tanox Biosystems HIV infection, AIDS, ARCAD-519 Tanox Biosystems HIV infection, AIDS, ARC Adefovir dipivoxilGilead Sciences HIV infection AL-721 Ethigen ARC, PGL (Los Angeles, CA)HIV positive, AIDS Alpha Interferon Glaxo Wellcome Kaposi's sarcoma, HIVin combination w/Retrovir Ansamycin Adria Laboratories ARC LM 427(Dublin, OH) Erbamont (Stamford, CT) Antibody which Advanced BiotherapyAIDS, ARC Neutralizes pH Concepts Labile alpha aberrant (Rockville, MD)Interferon AR177 Aronex Pharm HIV infection, AIDS, ARC Beta-fluoro-ddANat'l Cancer Institute AIDS-associated diseases CI-1012 Warner-LambertHIV-1 infection Cidofovir Gilead Science CMV retinitis, herpes,papillomavirus Curdlan sulfate AJI Pharma USA HIV infectionCytomegalovirus MedImmune CMV retinitis Immune globin Cytovene SyntexSight threatening Ganciclovir CMV peripheral CML retinitis DarunavirTibotec-J & J HIV infection, AIDS, ARC (protease inhibitor) DelaviridinePharmacia-Upjohn HIV infection, AIDS, ARC (RT inhibitor) Dextran SulfateUeno Fine Chem. AIDS, ARC, HIV Ind. Ltd. (Osaka, positive Japan)asymptomatic ddC Hoffman-La Roche HIV infection, AIDS, DideoxycytidineARC ddI Bristol-Myers Squibb HIV infection, AIDS, Dideoxyinosine ARC;combination with AZT/d4T DMP-450 AVID HIV infection, (Camden, NJ) AIDS,ARC (protease inhibitor) Efavirenz Bristol Myers Squibb HIV infection,(DMP 266, SUSTIVA ®) AIDS, ARC (-)6-Chloro-4-(S)- (non-nucleoside RTcyclopropylethynyl- inhibitor) 4(S)-trifluoro- methyl-1,4-dihydro-2H-3,1-benzoxazin- 2-one, STOCRINE EL10 Elan Corp, PLC HIV infection(Gainesville, GA) Etravirine Tibotec/J & J HIV infection, AIDS, ARC(non-nucleoside reverse transcriptase inhibitor) Famciclovir Smith Klineherpes zoster, herpes simplex GS 840 Gilead HIV infection, AIDS, ARC(reverse transcriptase inhibitor) HBY097 Hoechst Marion HIV infection,Roussel AIDS, ARC (non-nucleoside reverse transcriptase inhibitor)Hypericin VIMRx Pharm. HIV infection, AIDS, ARC Recombinant Human TritonBiosciences AIDS, Kaposi's Interferon Beta (Almeda, CA) sarcoma, ARCInterferon alfa-n3 Interferon Sciences ARC, AIDS Indinavir Merck HIVinfection, AIDS, ARC, asymptomatic HIV positive, also in combinationwith AZT/ddI/ddC ISIS 2922 ISIS Pharmaceuticals CMV retinitis KNI-272Nat'l Cancer Institute HIV-assoc. diseases Lamivudine, 3TC GlaxoWellcome HIV infection, AIDS, ARC (reverse transcriptase inhibitor);also with AZT Lobucavir Bristol-Myers Squibb CMV infection NelfinavirAgouron HIV infection, Pharmaceuticals AIDS, ARC (protease inhibitor)Nevirapine Boeheringer HIV infection, Ingleheim AIDS, ARC (RT inhibitor)Novapren Novaferon Labs, Inc. HIV inhibitor (Akron, OH) Peptide TPeninsula Labs AIDS Octapeptide (Belmont, CA) Sequence Trisodium AstraPharm. CMV retinitis, HIV Phosphonoformate Products, Inc. infection,other CMV infections PNU-140690 Pharmacia Upjohn HIV infection, AIDS,ARC (protease inhibitor) Probucol Vyrex HIV infection, AIDS RBC-CD4Sheffield Med. HIV infection, Tech (Houston, TX) AIDS, ARC RitonavirAbbott HIV infection, AIDS, ARC (protease inhibitor) SaquinavirHoffmann- HIV infection, LaRoche AIDS, ARC (protease inhibitor)Stavudine; d4T Bristol-Myers Squibb HIV infection, AIDS, Didehydrodeoxy-ARC Thymidine Tipranavir Boehringer Ingelheim HIV infection, AIDS, ARC(protease inhibitor) Valaciclovir Glaxo Wellcome Genital HSV & CMVInfections Virazole Viratek/ICN asymptomatic HIV Ribavirin (Costa Mesa,CA) positive, LAS, ARC VX-478 Vertex HIV infection, AIDS, ARCZalcitabine Hoffmann-LaRoche HIV infection, AIDS, ARC, with AZTZidovudine; AZT Glaxo Wellcome HIV infection, AIDS, ARC, Kaposi'ssarcoma, in combination with other therapies Tenofovir disoproxil,Gilead HIV infection, fumarate salt AIDS, (VIREAD ®) (reversetranscriptase inhibitor) EMTRIVA ® Gilead HIV infection, (Emtricitabine)(FTC) AIDS, (reverse transcriptase inhibitor) COMBIVIR ® GSK HIVinfection, AIDS, (reverse transcriptase inhibitor) Abacavir succinateGSK HIV infection, (or ZIAGEN ®) AIDS, (reverse transcriptase inhibitor)REYATAZ ® Bristol-Myers Squibb HIV infection (or atazanavir) AIDs,protease inhibitor FUZEON ® Roche/Trimeris HIV infection (Enfuvirtide orT-20) AIDs, viral Fusion inhibitor LEXIVA ® GSK/Vertex HIV infection (orFosamprenavir AIDs, viral protease calcium) inhibitor SELZENTRY ™ PfizerHIV infection Maraviroc; (UK 427857) AIDs, (CCR5 antagonist, indevelopment) TRIZIVIR ® GSK HIV infection AIDs, (three drug combination)Sch-417690 (vicriviroc) Schering-Plough HIV infection AIDs, (CCR5antagonist, in development) TAK-652 Takeda HIV infection AIDs, (CCR5antagonist, in development) GSK 873140 GSK/ONO HIV infection (ONO-4128)AIDs, (CCR5 antagonist, in development) Integrase Inhibitor Merck HIVinfection MK-0518 AIDs Raltegravir TRUVADA ® Gilead Combination ofTenofovir disoproxil fumarate salt (VIREAD ®) and EMTRIVA ®(Emtricitabine) Integrase Inhibitor Gilead/Japan Tobacco HIV InfectionGS917/JTK-303 AIDs Elvitegravir in development Triple drug combinationGilead/Bristol-Myers Squibb Combination of Tenofovir ATRIPLA ®disoproxil fumarate salt (VIREAD ®), EMTRIVA ® (Emtricitabine), andSUSTIVA ® (Efavirenz) FESTINAVIR ® Oncolys BioPharma HIV infection AIDsin development CMX-157 Chimerix HIV infection Lipid conjugate of AIDsnucleotide tenofovir G5K1349572 GSK HIV infection Integrase inhibitorAIDs TIVICAY ® dolutegravir IMMUNOMODULATORS AS-101 Wyeth-Ayerst AIDSBropirimine Pharmacia Upjohn Advanced AIDS Acemannan Carrington Labs,Inc. AIDS, ARC (Irving, TX) CL246, 738 Wyeth AIDS, Kaposi's Lederle Labssarcoma FP-21399 Fuki ImmunoPharm Blocks HIV fusion with CD4 + cellsGamma Interferon Genentech ARC, in combination w/TNF (tumor necrosisfactor) Granulocyte Genetics Institute AIDS Macrophage Colony SandozStimulating Factor Granulocyte Hoechst-Roussel AIDS Macrophage ColonyImmunex Stimulating Factor Granulocyte Schering-Plough AIDS, MacrophageColony combination Stimulating Factor w/AZT HIV Core Particle RorerSeropositive HIV Immunostimulant IL-2 Cetus AIDS, in combinationInterleukin-2 w/AZT IL-2 Hoffman-LaRoche AIDS, ARC, HIV, inInterleukin-2 Immunex combination w/AZT IL-2 Chiron AIDS, increase inInterleukin-2 CD4 cell counts (aldeslukin) Immune Globulin CutterBiological Pediatric AIDS, in Intravenous (Berkeley, CA) combinationw/AZT (human) IMREG-1 Imreg AIDS, Kaposi's (New Orleans, LA) sarcoma,ARC, PGL IMREG-2 Imreg AIDS, Kaposi's (New Orleans, LA) sarcoma, ARC,PGL Imuthiol Diethyl Merieux Institute AIDS, ARC Dithio CarbamateAlpha-2 Schering Plough Kaposi's sarcoma Interferon w/AZT, AIDSMethionine- TNI Pharmaceutical AIDS, ARC Enkephalin (Chicago, IL) MTP-PECiba-Geigy Corp. Kaposi's sarcoma Muramyl-Tripeptide Granulocyte AmgenAIDS, in combination Colony Stimulating w/AZT Factor Remune ImmuneResponse Immunotherapeutic Corp. rCD4 Genentech AIDS, ARC RecombinantSoluble Human CD4 rCD4-IgG AIDS, ARC hybrids Recombinant Biogen AIDS,ARC Soluble Human CD4 Interferon Hoffman-La Roche Kaposi's sarcoma Alfa2a AIDS, ARC, in combination w/AZT SK&F106528 Smith Kline HIV infectionSoluble T4 Thymopentin Immunobiology HIV infection Research Institute(Annandale, NJ) Tumor Necrosis Genentech ARC, in combination Factor; TNFw/gamma Interferon ANTI-INFECTIVES Clindamycin with Pharmacia Upjohn PCPPrimaquine Fluconazole Pfizer Cryptococcal meningitis, candidiasisPastille Squibb Corp. Prevention of Nystatin Pastille oral candidiasisOrnidyl Merrell Dow PCP Eflomithine Pentamidine LyphoMed PCP treatmentIsethionate (IM & IV) (Rosemont, IL) Trimethoprim AntibacterialTrimethoprim/sulfa Antibacterial Piritrexim Burroughs Wellcome PCPtreatment Pentamidine Fisons Corporation PCP prophylaxis Isethionate forInhalation Spiramycin Rhone-Poulenc Cryptosporidial diarrheaIntraconazole- Janssen-Pharm. Histoplasmosis; R51211 cryptococcalmeningitis Trimetrexate Warner-Lambert PCP Daunorubicin NeXstar, SequusKaposi's sarcoma Recombinant Human Ortho Pharm. Corp. Severe anemiaErythropoietin assoc. with AZT therapy Recombinant Human SeronoAIDS-related Growth Hormone wasting, cachexia Megestrol AcetateBristol-Myers Squibb Treatment of anorexia assoc. W/AIDS TestosteroneAlza, Smith Kline AIDS-related wasting Total Enteral Norwich EatonDiarrhea and Nutrition Pharmaceuticals malabsorption related to AIDS

Methods of Synthesis

The compounds of this invention can be made by various methods known inthe art including those of the following schemes and in the specificembodiments section. The structure numbering and variable numberingshown in the synthetic schemes are distinct from, and should not beconfused with, the structure or variable numbering in the claims or therest of the specification. The variables in the schemes are meant onlyto illustrate how to make some of the compounds of this invention. Thedisclosure is not limited to the foregoing illustrative examples and theexamples should be considered in all respects as illustrative and notrestrictive, reference being made to the appended claims, rather than tothe foregoing examples, and all changes which come within the meaningand range of equivalency of the claims are therefore intended to beembraced.

Abbreviations used in the schemes and examples generally followconventions used in the art. Chemical abbreviations used in thespecification and examples are defined as follows: “KHMDS” for potasiumbis(trimethylsilyl)amide; “DMF” for N,N-dimethylformamide; “HATU” forO-(t-Azabenzotriazol-1-yl)-N,N,N′,N′-tetramethyluroniumhexafluorophosphate, “MeOH” for methanol; “Ar” for aryl; “TFA” fortrifluoroacetic acid, “DMSO” for dimethylsulfoxide; “h” for hours; “rt”for room temperature or retention time (context will dictate); “min” forminutes; “EtOAc” for ethyl acetate; “THF” for tetrahydrofuran; “Et₂O”for diethyl ether; “DMAP” for 4-dimethylaminopyridine; “DCE” for1,2-dichloroethane; “ACN” for acetonitrile; “DME” for1,2-dimethoxyethane; “HOBt” for 1-hydroxybenzotriazole hydrate; and“DIEA” for diisopropylethylamine.

Certain other abbreviations as used herein, are defined as follows: “1×”for once, “2×” for twice, “3×” for thrice, “° C.” for degrees Celsius,“eq” for equivalent or equivalents, “g” for gram or grams, “mg” formilligram or milligrams, “L” for liter or liters, “mL” for milliliter ormilliliters, “μL” for microliter or microliters, “N” for normal, “M” formolar, “mmol” for millimole or millimoles, “atm” for atmosphere, “psi”for pounds per square inch, “conc.” for concentrate, “sat” or “sat'd“for saturated, “MW” for molecular weight, “mp” for melting point, “ee”for enantiomeric excess, “MS” or “Mass Spec” for mass spectrometry,“ESI” for electrospray ionization mass spectroscopy, “HR” for highresolution, “HRMS” for high resolution mass spectrometry, “LCMS” forliquid chromatography mass spectrometry, “HPLC” for high pressure liquidchromatography, “RP HPLC” for reverse phase HPLC, “TLC” or “tlc” forthin layer chromatography, “NMR” for nuclear magnetic resonancespectroscopy, “¹H” for proton, “8” for delta, “s” for singlet, “d” fordoublet, “t” for triplet, “q” for quartet, “m” for multiplet, “br” forbroad, “Hz” for hertz, and “a”, “3”, “R”, “S”, “E”, and “Z” arestereochemical designations familiar to one skilled in the art.

Some compounds of this invention can be prepared by the methods outlinedin the Scheme I

Some compounds of this invention can be prepared by the methods outlinedin the Scheme II.

The compounds described herein were purified by the methods well knownto those skilled in art by normal phase column chromatography on silicagel column using appropriate solvent system described. Preparative HPLCpurifications mentioned in this experimentation section were carried outgradient elution either on Sunfire Prep C18 ODB column (5 μm; 19 or30×100 mm) or Waters Xbridge C18 column (5 μM; 19×200 or 30×100 mm) orWater Atlantis (5 μm; 19 or 30×100 mm) using the following mobilephases. Mobile phase A: 9:1 H₂O/acetonitrile with 10 mM NH₄OAc andmobile phase B:A:9:1 acetonitrile/H₂O with 10 mM NH₄OAc; or mobile phaseA: 9:1 H₂O/acetonitrile with 0.1% TFA and mobile phase B:A:9:1acetonitrile/H₂O with 0.1% TFA; or mobile phase A: water/MeOH (9:1) with20 mM NH₄OAc and mobile phase B: 95:5 MeOH/H₂O with 20 mM NH₄OAc ormobile phase A: water/MeOH (9:1) with 0.1% TFA and mobile phase B: 95:5MeOH/H₂O with 0.1% TFA or mobile Phase A: 5:95 acetonitrile: water with10-mM ammonium acetate; Mobile Phase B: 95:5 acetonitrile: water with10-mM ammonium acetate.

All Liquid Chromatography (LC) data were recorded on a Shimadzu LC-10ASor LC-20AS liquid chromotograph using a SPD-10AV or SPD-20A UV-Visdetector and Mass Spectrometry (MS) data were determined with aMicromass Platform for LC in electrospray mode.

Compounds purified by preparative HPLC were diluted in methanol (1.2 mL)or DMF and purified using a Shimadzu LC-8A or LC-10A automatedpreparative HPLC system.

3,5-Dibromo-2,6-dimethylpyridin-4-ol

A 3-neck R.B-flask equipped with mechanical stirrer, addition funnel andcondenser is charged with 2,6-dimethylpyridin-4-ol (100 g, 812 mmol),CH₂Cl₂ (1000 mL) and MeOH (120 mL). To the resulting light brown or tansolution was added tert-BuNH2 (176 ml, 1665 mmol), cooled in water bathmaintained between 5-10° C. (ice-water) and added drop wise Br2 (84 ml,1624 mmol) over 70 min. After the addition was complete cold bath wasremoved and stirred for 1.5 h at rt. Then, the light orange slurry wasfiltered and the filter cake was washed with ether (250 mL) and dried toafford 3,5-dibromo-2,6-dimethylpyridin-4-ol, hydrobromide (280.75 g, 776mmol, 96% yield) as white solid which was used in the next step withoutfurther purification. ¹H NMR (500 MHz, DMSO-d₆) δ 12.08 (br. s., 1H),2.41 (s, 6H). LCMS (M+H)=281.9.

Alternative Procedure:

Bromine (72.8 mL, 1.4 mol) was added via addition funnel over 60 min toa mechanically stirred cold (ice-water bath) solution of2,6-dimethylpyridin-4-ol (87 g, 706 mmol) and 4-methylmorpholine (156mL, 1.4 mol) in dichloromethane (1 L) and methanol (100 mL) and thenstirred for 2 h at rt. Additional bromine (˜15 mL) was added based onmonitoring by LCMS. The product was filtered, washed with ether, anddried under vacuum to give 3,5-dibromo-2,6-dimethylpyridin-4-ol 176.8 g(88%).

3,5-Dibromo-4-chloro-2,6-dimethylpyridine

Triethylamine (28.8 mL, 206 mmol) was added to a nitrogen purgedsolution of 3,5-dibromo-2,6-dimethylpyridin-4-ol (58 g, 206 mmol) andphosphorous oxychloride (57.7 mL, 619 mmol) in chloroform (450 mL) andstirred for 1 h at rt, then 3 h at 80° C. The reaction was removed fromheating and immediately concentrated under house vacuum; then under highvacuum. The appearance was a cream colored solid, which was azeotropedwith toluene (2×100 mL); treated with ice (200 g) for 10 min andcarefully neutralized with NaHCO₃ (powder), and 1N NaOH solution, andextracted with DCM (2×400 mL). The combined organic layers were dried(MgSO₄), concentrated, and a beige solid was obtained that was washedwith hexanes and dried under high vacuum to give3,5-dibromo-4-chloro-2,6-dimethyl-pyridine 52.74 g (85.1%).Concentration of the hexanes gave 3.5 g of less pure product. ¹H NMR(500 MHz, CDCl₃) δ 2.59 (s, 6H). LCMS (M+H)=300.0.

Ethyl 2-(5-bromo-4-chloro-2,6-dimethylpyridin-3-yl)-2-oxoacetate

To a stirred mixture of 3,5-dibromo-4-chloro-2,6-dimethylpyridine (14.94g, 49.9 mmol) and Cu(I)Br Me2S (0.513 g, 2.495 mmol) in THF (50 mL) wasadded drop wise 2M iPrMgCl/THF (26.2 ml, 52.4 mmol) at −30° C. over 5min. Then, the resulting slurry was warmed to −10° C. over 30 min andstirred for 30 min. The homogeneous brown reaction mixture was rapidlytransferred via cannula to a solution of ethyl 2-chloro-2-oxoacetate(6.14 ml, 54.9 mmol, degassed for 5 min by bubbling N2 through thesolution) in THF (50 mL) maintained at −30° C. The resulting reactionmixture was stirred (1.5 h) while warming to 0° C. Then, taken up in toEt₂O (200 mL), washed with 1:1 sat Na₂CO₃/1M NH₄Cl (3×50 mL), dried(MgSO₄), filtered and concentrated to give brown viscous oil. Flashchromatography using 2.5, 5 and 7.5% EtOAc/Hex afforded ethyl2-(5-bromo-4-chloro-2,6-dimethylpyridin-3-yl)-2-oxoacetate (14.37 g,44.8 mmol, 90% yield) as white solid. ¹H NMR (400 MHz, CDCl₃) δ 4.42 (q,J=7.0 Hz, 2H), 2.76 (s, 3H), 2.46 (s, 3H), 1.41 (t, J=7.2 Hz, 3H). LCMS(M+H)=322.1.

Ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetate

To a solution of 4,4-dimethylpiperidine (1.245 g, 11.00 mmol) and DIEA(3.49 ml, 20.00 mmol) in anhydrous CH₃CN (40 mL) was added ethyl2-(5-bromo-4-chloro-2,6-dimethylpyridin-3-yl)-2-oxoacetate (3.21 g, 10mmol) at rt. The resulting mixture was placed in a pre-heated oil bath(80° C.). After 22 h, the reaction mixture was concentrated and theresidue was purified by flash chromatography using 1-lit each 2.5, 5,7.5 and 10% EtOAc/Hex to afford ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetate(2.846 g, 7.16 mmol, 71.6% yield) as yellow solid. ¹H NMR (500 MHz,CDCl₃) δ 4.37 (q, J=7.1 Hz, 2H), 3.67-2.75 (br.s., 4H), 2.71 (s, 3H),2.44 (s, 3H), 1.42 (t, J=7.1 Hz, 3H), 1.38 (t, J=5.6 Hz, 4H), 1.00 (s,6H). LCMS (M+H)=399.4.

(S)-Ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate

To stirred yellow solution of ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetate(2.25 g, 5.66 mmol) and(R)-1-methyl-3,3-diphenylhexahydropyrrolo[1,2-c][1,3,2]oxazaborole(0.314 g, 1.133 mmol) in toluene (30 mL) at −35° C. was added drop wise50% catecholborane (1.819 ml, 8.49 mmol) over 10 min. The reactionmixture was slowly warmed to −15° C. over 1 h and then left for 2 h at−15° C. Then, diluted with EtOAc (100 mL), washed with sat Na₂CO₃ (4×25mL) by vigorously stirring and separating aqueous layers. The organiclayer dried (MgSO₄), filtered, concentrated and purified by flashchromatography using 10, 20 and 25% EtOAc/Hex to afford desired(S)-ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate(2.2596 g, 5.66 mmol, 100% yield) contaminated with about 10% of(S)-ethyl2-(5-bromo-4-chloro-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate. Used inthe next step without further purification. ¹H NMR (500 MHz, CDCl₃) δ5.71 (d, J=7.3 Hz, 1H), 5.54 (d, J=7.4 Hz, 1H), 4.29 (dq, J=10.8, 7.1Hz, 1H), 4.16 (dq, J=10.8, 7.1 Hz, 1H), 3.94-3.83 (m, 2H), 2.71 (d,J=11.9 Hz, 1H), 2.67 (s, 3H), 2.59 (s, 3H), 2.54 (d, J=12.0 Hz, 1H),1.71 (td, J=12.7, 4.7 Hz, 1H), 1.62 (td, J=13.0, 4.7 Hz, 1H), 1.42 (dd,J=13.1, 2.2 Hz, 1H), 1.37 (dd, J=12.9, 2.4 Hz, 1H), 1.25 (t, J=7.1 Hz,3H), 1.09 (s, 3H), 1.04 (s, 3H). LCMS (M+H)=401.3.

(S)-Ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate

A stirred ice-cold yellow mixture of (S)-ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate(2.45 g, 6.14 mmol) and 70% HClO₄ (1.054 ml, 12.27 mmol) in CH₂Cl₂ (100mL) was saturated with isobutylene gas by bubbling through the reactionmixture (10 min). After 2 h, cold bath was removed and the turbidreaction mixture stirred for 22 h at rt. LCMS at this point showed 4:1product to sm. So, saturated with isobutylene (5 min) at rt and stirredfor additional 24 h. Then, neutralized with sat. Na₂CO₃ (30 mL), organiclayer separated and aqueous layer extracted with CH₂Cl₂ (25 mL). Thecombined organic layers dried (MgSO₄), filtered, concentrated andpurified by flash chromatography using 5, 10, 15, 20 and 40% EtOAc/hexto afford (S)-ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate(2.3074 g, 5.07 mmol, 83% yield) as yellow oil: ¹H NMR (500 MHz, CDCl₃)δ 6.19 (br. s., 1H), 4.17-4.24 (m, 1H), 4.08-4.14 (m, 1H), 4.04 (dt,J=2.5, 12.1 Hz, 1H), 3.51 (dt, J=2.5, 12.1 Hz, 1H), 2.85-2.91 (m, 1H),2.64 (s, 3H), 2.57-2.62 (m, 1H), 2.55 (s, 3H), 1.55-1.66 (m, 2H),1.41-1.46 (m, 1H), 1.32-1.37 (m, 1H), 1.21 (s, 9H), 1.20 (t, J=7.2 Hz,2H), 1.08 (s, 3H), 1.03 (s, 3H). LCMS (M+H)=457.4. And (S)-ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate(0.3 g, 0.751 mmol, 12.24% yield) as pale yellow paste: LCMS(M+H)=401.3.

Isopropyl 2-chloro-2-oxoacetate

The propan-2-ol (38.2 mL, 499 mmol) was added drop wise over 15 min to acold (0° C.), nitrogen purged solution of oxalyl dichloride (101 g, 799mmol) and the reaction was stirred at room temperature for 2.5 h. Then areflux condenser was fitted and a slight vacuum was applied for about 1h until HCl gas was removed (the HCl was trapped in by a sat'd solutionof NaHCO₃). The reflux condenser was removed and the flask was fittedwith a short path distillation head. Excess reagent was removed bydistillation under house vacuum (oil bath heated to 65° C.), and thenthe temperature was raised to between 85-95° C. and the product wasdistilled (NOTE: The 1^(st) fraction of ˜5 mL was discarded) to provideisopropyl 2-chloro-2-oxoacetate 52.62 g (70%).

Isopropyl 2-(5-bromo-4-chloro-2,6-dimethylpyridin-3-yl)-2-oxoacetate

A solution of 2M isopropyl magnesium chloride (84 mL, 168 mmol) wasadded drop wise over 20 min to a cold (−70° C.), nitrogen purgedsolution of 3,5-dibromo-4-chloro-2,6-dimethylpyridine (48 g, 160 mmol)and copper(I)bromide-dimethyl sulfide complex (1.65 g, 8.02 mmol) in THF(240 mL), which was then allowed to warm to −10° C. over 60 min. Thereaction mixture was transferred via cannula into a 1 L RB-flaskcontaining isopropyl 2-chloro-2-oxoacetate (26.6 g, 176 mmol) in THF(160 mL) maintained at −60° C., and the reaction stirred an additional2.5 h while being allowed to warm to −10° C. The reaction was quenchedupon diluted with a mixture of 10% NH₄Cl solution (80 mL) in ether (320mL). The organic layer was washed with 160 mL of sat'd NaHCO₃/10% NH₄Clsolution (1:1), brine, and dried (Na₂SO₄). The crude product was charged(DCM solution) to a 330 g ISCO silica gel cartridge and gradient eluted(5-20% EtOAc/hexanes) using an Isolera chromatography station gaveisopropyl 2-(5-bromo-4-chloro-2,6-dimethylpyridin-3-yl)-2-oxoacetate40.38 g (76%). ¹H NMR (500 MHz, CDCl₃) δ 5.28-5.21 (m, 1H), 2.77 (s,3H), 2.47 (s, 3H), 1.40 (d, J=6.3 Hz, 6H). LCMS (M+H)=336.04.

Isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetate

To a stirred solution of isopropyl2-(5-bromo-4-chloro-2,6-dimethylpyridin-3-yl)-2-oxoacetate (7.2 g, 21.52mmol) and DIEA (4.13 mL, 23.67 mmol) in anhydrous acetonitrile (15 mL)was added 4,4-dimethylpiperidine (2.68 g, 23.67 mmol) in acetonitrile(15 mL). The resulting solution was placed in a pre-heated oil bath at75° C. After heating (75-78° C.) for 24 h and the temperature was raisedto 85° C. for 24 h. Another portion of DIEA (3.5 mL, 20.04 mmol) and4,4-dimethylpiperidine (0.27 g, 2.4 mmol) in acetonitrile (3 mL) wasadded and hearted at 85° C. for a day. The reaction mixture was dilutedwith ether (100 mL), washed with water (100 mL), brine (50 mL), dried(MgSO₄), filtered, concentrated and purified by ISCO 120 g cartridge(EtOAc/hex: 0 to 20%) to afford isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetate(6.8 g, 16.53 mmol, 77% yield. ¹H NMR (500 MHz, CDCl₃) δ 5.25-5.11 (m,1H), 3.17 (br. s., 4H), 2.71 (s, 3H), 2.41 (s, 3H), 1.42-1.37 (m, 10H),1.00 (s, 6H).). LCMS (M+H)=413.3.

(S)-Isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate

To a yellow solution of isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetate(7.7 g, 18.72 mmol) and(R)-1-methyl-3,3-diphenylhexahydropyrrolo[1,2-c][1,3,2]oxazaborole (7.5mL, 7.50 mmol) in anhydrous toluene (100 mL) was added drop wise 50%catecholborane/toluene (6 mL, 28.0 mmol) over 5 min at −50° C. Then, thereaction mixture was slowly warmed to −30° C. over 1 h and left inrefrigerator (−20° C.) for 3 days. Then, the reaction mixture wasdiluted with EtOAc (100 mL) and 20 mL of 1M Na₂CO₃, and vigorouslystirred for 30 min. Aqueous layer separated and organic layer washedwith sat'd Na₂CO₃ (2×25 mL) by vigorously stirring for 15 each time,then dried (MgSO₄), filtered and concentrated to give crude product aslight purple paste which was purified by flash chromatography using 0 to40% EtOAc/hex to afford (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate(6.7 g, 15.72 mmol, 84% yield) as colorless thick paste. ¹H NMR (500MHz, CDCl₃) δ 5.85 (d, J=5.7 Hz, 1H), 5.59 (d, J=7.4 Hz, 1H), 5.08 (dt,J=12.5, 6.3 Hz, 1H), 3.98-3.88 (m, 1H), 3.88-3.78 (m, 1H), 2.76-2.68 (m,1H), 2.67 (s, 3H), 2.64-2.58 (m, 1H), 2.57 (s, 3H), 1.73 (td, J=12.8,4.8 Hz, 1H), 1.65-1.59 (m, 1H), 1.47-1.35 (m, 2H), 1.27 (d, J=6.3 Hz,3H), 1.17 (d, J=6.1 Hz, 3H), 1.09 (s, 3H), 1.04 (s, 3H). LCMS(M+H)=414.6.

(S)-Isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate

A stirred ice-cold yellow mixture of (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate(6.7 g, 16.21 mmol) and 70% HClO₄ (2.2 mL, 25.6 mmol) in dichloromethane(400 mL) was saturated with isobutylene gas by bubbling through thereaction mixture (10 min). The reaction mixture was cloudy sealed in aseal tube, stirred for 24 h at rt. The reaction mixture was recooled ina −10° C. bath, bubbled additional isobutylene (˜15 min). The reactionmixture became a clear solution at this point. The tube was sealed andstirred at rt for 16 h. LCMs at this point showed incomplete reaction.So, the reaction mixture was cooled down to −30° C. and bubbledisobutene (˜15 min). After 24 h, reaction mixture was neutralized withsat. Na₂CO₃ (20 mL), organic layer separated and aqueous layer wasextracted with CH₂Cl₂ (25 mL). The combined organic layers were dried(MgSO₄), filtered, concentrated and purified on a ISCO 120 g column(EtOAc/hex: 0 to 40%) to afford (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate(5.43 g, 9.83 mmol, 60.7% yield) as a viscous oil. ¹H NMR (500 MHz,CDCl₃) δ 6.26 (br. s., 1H), 5.09-4.97 (m, 1H), 4.06 (br. s., 1H), 3.51(br. s., 1H), 2.90 (br. s., 1H), 2.65 (s, 3H), 2.56 (s, 3H), 1.72-1.54(m, 3H), 1.47 (br. s., 1H), 1.37 (br. s., 1H), 1.23-1.20 (m, 12H), 1.15(d, J=6.1 Hz, 3H), 1.09 (br. s., 3H), 1.04 (br. s., 3H). LCMS(M+H)=471.3.

6-Bromo-2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinoline

To a solution of 6-bromo-1,2,3,4-tetrahydroisoquinoline (1.25 g, 5.88mmol) in DCM (25 mL) was added 2-chloro-6-methylbenzaldehyde (1.0 g, 6.5mmol) and acetic acid (0.337 mL, 5.88 mmol) in DCM (25 mL). Then sodiumtriacetoxyborohydride (1.62 g, 7.64 mmol) was added. The mixture wasstirred at r.t for 16 hrs. The mixture was quenched with water andextracted with EtOAc. The organic layer was washed with brine, driedover Na₂SO₄ and concentrated. The residue was purified byrecrystallization with EtOAc to give6-bromo-2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinoline (1.44g, 4.11 mmol, 69.8% yield). LCMS (M+H): 350.00, 352.00. ¹H NMR (400 MHz,DMSO-d₆) δ 7.32-7.14 (m, 5H), 6.99 (d, J=8.1 Hz, 1H), 3.77 (s, 2H), 3.56(s, 2H), 2.78-2.72 (m, 2H), 2.71-2.66 (m, 2H), 2.41 (s, 3H).

6-Bromo-2-(2-fluoro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinoline

This compound is prepared by the procedure described above for6-bromo-2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinoline. ¹HNMR (400 MHz, DMSO-d₆) δ 7.30-7.19 (m, 3H), 7.01 (dd, J=17.4, 7.6 Hz,3H), 3.63 (d, J=2.2 Hz, 2H), 3.52 (s, 2H), 2.79-2.73 (m, 2H), 2.69-2.63(m, 2H), 2.38 (s, 3H). LCMS (M+H)=336.1

2-(2-Chloro-6-methylbenzyl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4-tetrahydroisoquinoline

6-Bromo-2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinoline (1.00g, 2.85 mmol),4,4,4′,4′,5,5,5′,5′-octamethyl-2,2′-bi(1,3,2-dioxaborolane) (1.09 g,4.28 mmol), Pd(dppf)Cl₂ (0.209 g, 0.285 mmol) and potassium acetate(0.840 g, 8.55 mmol) were combined in dioxane (10 mL) in a sealedbottle. The mixture was degassed and heated at 85° C. for 8 hrs. Themixture was diluted with EtOAc, washed with water, brine, dried overMgSO₄ and concentrated. The residue was purified by silica gel column(EtOAc/hexanes gradient) to give2-(2-chloro-6-methylbenzyl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4-tetrahydroisoquinoline(1.05 g, 2.64 mmol, 93% yield). 1H NMR (400 MHz, CDCl₃) δ 7.57-7.51 (m,2H), 7.23 (d, J=7.6 Hz, 1H), 7.14-7.06 (m, 2H), 7.02 (d, J=7.6 Hz, 1H),3.83 (s, 2H), 3.71 (s, 2H), 2.88-2.76 (m, 4H), 2.46 (s, 3H), 1.34 (s,12H). LCMS (M+H): 398.05.

2-(2-Fluoro-6-methylbenzyl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4-tetrahydroisoquinoline

This compound is prepared using6-bromo-2-(2-fluoro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinoline byfollowing the procedure described above for2-(2-chloro-6-methylbenzyl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4-tetrahydroisoquinoline.LCMS (M+H)=382.2.

Preparation of Intermediates (S)-ethyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetateand(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)aceticacid from (S)-ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate

Step 1: To a mixture of (S)-ethyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate(500 mg),(2-(tert-butoxycarbonyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)boronic acid(365 mg) and Cs₂CO₃ (715 mg) in 1,4-dioxane (25 mL) and water (5 mL) wasadded Pd(PPh₃)₄ (127 mg). The mixture was flushed with nitrogen and thenheated at 85° C. for 3 hours. The mixture was diluted with water (20 mL)and then extracted with EtOAc (2×20 mL). The organic layers werecombined, washed with brine and concentrated under vacuum to give acrude of (S)-tert-butyl6-(5-(1-(tert-butoxy)-2-ethoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-3,4-dihydroisoquinoline-2(1H)-carboxylatewhich was used as was. LCMS: MS (M+H)⁺ calcd. 608.4; observ. 608.5.

Step 2: To a solution of (S)-tert-butyl6-(5-(1-(tert-butoxy)-2-ethoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-3,4-dihydroisoquinoline-2(1H)-carboxylate(200 mg) in CH₂Cl₂ (20 mL) was added TFA (1 mL). The reaction wasstirred at room temperature for 3 hours. All the solvents were removedunder vacuum to give rude (S)-ethyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetatewhich was used without further purification. LCMS: MS (M+H)⁺ calcd.508.4; observ. 508.3.

Step 3: To a solution of (S)-ethyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetate(10 mg) in MeOH (1 mL) and THF (1 mL) was added sodium hydroxide (0.158mL, 1N). The reaction was stirred at 80° C. for 2 hours. The mixture wasacidified by 1N HCl to pH ˜4. All the solvents were removed under vacuumto give a residue was purified by preparative HPLC system. LCMS: MS(M+H)⁺ calcd. 480.3; observ. 480.3.

Preparation of Intermediates (S)-isopropyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetateand(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)aceticacid from (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate

Step 1: To a mixture of (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate(1.1 g),(2-(tert-butoxycarbonyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)boronic acid(0.649 g) and Cs₂CO₃ (1.527 g) in 1,4-dioxane (40 mL) and water (8 mL)was added Pd(PPh₃)₄ (0.271 g). The mixture was flushed with nitrogen andthen heated at 85° C. for 5 hours. The mixture was diluted with water(50 mL) and then extracted with EtOAc (2×50 mL). The organic layers werecombined, washed with brine and concentrated under vacuum to give aresidue which was purified by silica gel chromatography(hexane/EtOAc=10:1 to 3:1) to give (S)-tert-butyl6-(5-(1-(tert-butoxy)-2-isopropoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-3,4-dihydroisoquinoline-2(1H)-carboxylate.LCMS: MS (M+H)+ calcd. 622.4; observ. 622.4.

Step 2: To a solution of (S)-tert-butyl6-(5-(1-(tert-butoxy)-2-isopropoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-3,4-dihydroisoquinoline-2(1H)-carboxylate(420 mg) in CH₂Cl₂ (5 mL) was added TFA (1 mL). The reaction mixture wasstirred at room temperature for 4 hours. All the solvents were removedunder vacuum to give (S)-isopropyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetatewhich was used without further purification. LCMS: MS (M+H)⁺ calcd.522.4; observ. 522.3.

Step 3: To a solution of (S)-isopropyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetate(50 mg) in ethanol (4 mL) was added KOH (43.0 mg) and water (0.4 mL).The reaction mixture was heated at 85° C. for 6 hours. The mixture wasacidified by 1N HCl to pH=4. All the solvents were removed under vacuum.The residue was used without further purification. LCMS: MS (M+H)⁺calcd. 480.3; observ. 480.2.

General Procedure A for the preparation of Claim I, from (S)-ethyl or(S)-isopropyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetate

Step 1: Na₂CO₃ or K₂C₀₃ or Cs₂CO₃ or NaH (1-20 eq.) was added into asolution of (S)-ethyl of (S)-isopropyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetate(1 eq.) and an electrophile (1-20 eq.) in acetonitrile or THF or DMF ordioxane. The reaction was carried out at room temperature or at anincreased temperature (up to 150° C.) for a period of time (10 minutesto 72 hours). After removal of solvents under vacuum, the residue wasused as was or purified by the preparative HPLC system.

Step 2: To a solution of the product from the step 1 (1 eq.) in MeOH orEtOH and THF (volume ratio 20:1 to 1:20) was added NaOH or KOH (1 to 100eq.). The reaction was carried out at room temperature or at anincreased temperature (up to 150° C.) for a period of time (10 minutesto 72 hours). The mixture was acidified by 1N HCl to pH ˜4. Removal ofthe solvents under vacuum gave a residue which was purified by thepreparative HPLC system.

General Procedure B for the preparation of Claim I, from (S)-ethyl or(S)-isopropyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetate

Step 1: A solution of (S)-Ethyl or (S)-isopropyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetate(1 eq.) and an aldehyde (1-10 eq.) in DMF was stirred at roomtemperature for 2-24 hours, before NaCNBH₃ (1-20 eq.) and AcOH (1-200eq.) were added. The reaction was carried out at room temperature or atan increased temperature (up to 150° C.) for a period of time (10minutes to 72 hours). After the reaction was quenched with water, it wasextracted with EtOAc. The combined organic layer was washed with water,brine, dried over MgSO₄ and concentrated under vacuum. The residue wasused as was or purified by the preparative HPLC system.

Step 2: To a solution of the product from the step 1 (1 eq.) in MeOH orEtOH and THF (volume ratio 20:1 to 1:20) was added NaOH or KOH (1 to 100eq.). The reaction was carried out at room temperature or at anincreased temperature (up to 150° C.) for a period of time (10 minutesto 72 hours). The mixture was acidified by 1N HCl to pH ˜4. Removal ofthe solvents under vacuum gave a residue which was purified by thepreparative HPLC system.

General Procedure C for the preparation of Claim I, from(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)aceticacid

A solution of(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)aceticacid (1 eq.) and an aldehyde (1-10 eq.) in DMF was stirred at roomtemperature for 2-24 hours, before NaCNBH₃ (1-20 eq.) and AcOH (1-200eq.) were added. The reaction was carried out at room temperature or atan increased temperature (up to 150° C.) for a period of time (10minutes to 72 hours). After the reaction was quenched with water, it wasextracted with EtOAc. The combined organic layer was washed with water,brine, dried over MgSO₄ and concentrated under vacuum. The residue wasused as was or purified by the preparative HPLC system.

General Procedure D for the preparation of Claim I, from(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)aceticacid

Step 1: To a mixture of (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate(1 equiv),2-(arylalkyl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4-tetrahydroisoquinoline(1 to 5 equiv.) and cesium carbonate (2 to 10 equiv.) in1,4-dioxane/water was added Pd(Ph₃P)₄ (0.1 to 1 equiv.). The mixture wasflushed with nitrogen and then heated at 90° C. until reaction complete(1 to 24 h). The mixture was diluted with water and then extracted withEtOAc. The organic layers were combined, washed with brine andconcentrated to give a residue, which was purified by silicagel column(EtOAc/Hex; gradient elution) to give (S)-isopropyl2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(arylalkyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetate

Step 2: To a solution of the product from the step 1 (1 eq.) in MeOH orEtOH and THF (volume ratio 20:1 to 1:20) was added NaOH or KOH (1 to 100eq.). The reaction was carried out at room temperature or at anincreased temperature (up to 150° C.) for a period of time (10 minutesto 72 hours). The mixture was acidified by 1N HCl to pH ˜4. Removal ofthe solvents under vacuum gave a residue which was purified by thepreparative HPLC system.

Name General Method Used LCMS Compound Structure (M + H)⁺ 1(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 588.7 2(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 638.8 3(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 584.8 4(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 584.2 5(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 584.4 6(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 600.3 7(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 588.2 8(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 638.4 9(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 588.8 10(S)-3-((6-(5-(tert-butoxy(carboxy)methyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-3,4-dihydroisoquinolin-2(1H)-yl)methyl)benzoic acid

Method A: LCMS (M + H) = 614.2 11(S)-2-(5-(2-([1,1′-biphenyl]-3-ylmethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetic acid

Method A: LCMS (M + H) = 646.4 12(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 638.3 13(2S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(1-phenylethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 584.3 14(S)-2-(5-(2-([1,1′-biphenyl]-4-ylmethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetic acid

Method A: LCMS (M + H) = 646.4 15(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-methyl-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 652.1 16(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-methyl-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 652.1 17(S)-2-(tert-butoxy)-2-(5-(2-(3,4-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 598.1 18(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 602.3 19(S)-2-(tert-butoxy)-2-(5-(2-(2,4-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 598.5 20(S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: ¹H NMR (500 MHz, DMSO-d₆) δ 7.56-7.49 (m, 1H), 7.23 (t, J =9.7 Hz, 1H), 7.12-7.03 (m, 3H), 6.88 (s, 1H), 5.82 (d, J = 10.6 Hz, 1H),3.71 (s, 2H), 3.64 (br. s., 2H), 3.32 (br. s., 1H), 2.89 (s, 1H), 2.83(d, J = 4.8 Hz, 2H), 2.74-2.70 (m, 2H), 2.54 (s, 1H), 2.42 (s, 3H),2.09-2.04 (m, 3H), 1.90 (s, 6H), 1.11 (s, 9H), 0.84 (br. s., 3H), 0.60(br. s., 3H). LCMS (M + H) = 606.3 21(S)-2-(tert-butoxy)-2-(5-(2-(2,3-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: ¹H NMR (500 MHz, DMSO-d₆) δ 7.40-7.28 (m, 2H), 7.22 (d, J =5.5 Hz, 1H), 7.16-7.08 (m, 1H), 7.07-7.01 (m, 1H), 6.88 (s, 1H), 5.79(d, J = 10.3 Hz, 1H), 3.81-3.75 (m, 2H), 3.66 (br. s., 2H), 3.40-3.36(m, 1H), 2.91-2.68 (m, 6H), 2.54 (s, 1H), 2.42 (s, 3H), 2.12-2.01 (m,3H), 1.90 (s, 5H), 1.11 (s, 9H), 0.84 (br. s., 3H), 0.60 (br. s., 3H).LCMS (M + H) = 606.3 22(S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-3-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 622.3 23(S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C, D: ¹H NMR (500 MHz, METHANOL-d₄) δ 7.32-7.25 (m, 1H),7.25-7.07 (m, 4H), 6.99-6.90 (m, 1H), 5.60-5.41 (m, 1H), 3.94 (s, 2H),3.80 (s, J = 15.1 Hz, 2H), 2.91 (m, 4H), 2.81- 2.60 (m, 7H), 2.52 (s,3H), 2.31 (s, 3H), 1.35 (br. s., 4H), 1.20 (s, 9H), 0.85 (s, 6H). LCMS(M + H) = 618.3 24(S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: ¹H NMR (500 MHz, DMSO-d₆) δ 7.60-7.53 (m, 1H), 7.39 (d, J =8.8 Hz, 2H), 7.15-7.02 (m, 2H), 6.90-6.84 (m, 1H), 5.82 (d, J = 11.0 Hz,1H), 3.70-3.58 (m, 4H), 2.91-2.66 (m, 8H), 2.42 (s, 3H), 2.12-2.04 (m,3H), 1.90 (s, 4H), 1.11 (s, 9H), 0.85 (br. s., 3H), 0.61 (br. s., 3H).LCMS (M + H) = 622.3 25(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: ¹H NMR (500 MHz, DMSO-d₆) δ 7.36-7.26 (m, 1H), 7.13-6.93 (m,4H), 6.85 (br. s., 1H), 5.77 (d, J = 12.5 Hz, 1H), 3.59 (br. s., 4H),2.90-2.66 (m, 6H), 2.42 (s, 3H), 2.35 (br. s., 3H), 2.12-2.03 (m, 3H),1.90 (s, 7H), 1.10 (br. s., 9H), 0.84 (br. s., 3H), 0.59 (br. s., 3H).LCMS (M + H) = 602.4 26(S)-2-(tert-butoxy)-2-(5-(2-(3,5-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 638.4 27(S)-2-(tert-butoxy)-2-(5-(2-(4-(tert-butyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 626.5 28(S)-2-(tert-butoxy)-2-(5-(2-(3-chlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 604.4 29(S)-2-(tert-butoxy)-2-(5-(2-(2,5-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 598.4 30(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 656.5 31(S)-2-(tert-butoxy)-2-(5-(2-(3,5-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 606.3 32(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 656.3 33(S)-2-(tert-butoxy)-2-(5-(2-(2,6-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 598.4 34(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3,4,5-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A, C: LCMS (M + H) = 624.3 35(S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-4-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 622.0 36(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-isopropylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 612.5 37(S)-2-(tert-butoxy)-2-(5-(2-(3,4-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 606.5 38(S)-2-(tert-butoxy)-2-(5-(2-(2,5-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 606.5 39(S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 622.4 40(S)-2-(tert-butoxy)-2-(5-(2-(2,3-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 638.3 41(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,3,4-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A, C: LCMS (M + H) = 624.3 42(S)-2-(tert-butoxy)-2-(5-(2-(5-chloro-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 622.3 43(S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-5-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 622.4 44(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,3,6-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 624.5 45(S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-5-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 622.4 46(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-5-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 602.5 47(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-fluoro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 602.5 48(S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluoro-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 620.5 49(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,4,5-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 624.4 50(S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 606.5 51(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A, D: ¹H NMR (400 MHz, DMSO-d₆) δ 7.28-7.19 (m, 1H), 7.15-6.98(m, 4H), 6.87 (s, 1H), 5.96 (br. s., 1H), 4.94 (td, J = 6.2, 3.4 Hz,1H), 3.68 (br. s., 2H), 3.64 (br. s., 2H), 2.88-2.67 (m, 6H), 2.44-2.39(m, 6H), 2.10 (s, 2H), 2.05 (s, 1H), 1.82 (t, J = 11.4 Hz, 1H), 1.51-1.41 (m, 1H), 1.25 (d, J = 13.2 Hz, 1H), 1.17 (dd, J = 6.2, 1.3 Hz, 4H),1.15-1.09 (m, 14H), 0.84 (s, 3H), 0.59 (s, 3H). LCMS (M + H) = 644.3.LCMS (M + H) = 602.5 52(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-methyl-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 652.5 53(S)-2-(tert-butoxy)-2-(5-(2-(2,4-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 638.4 54(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 602.5 55(S)-2-(tert-butoxy)-2-(5-(2-(2-chlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 604.5 56(S)-2-(tert-butoxy)-2-(5-(2-(4-chlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 604.4 57(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,4,6-trimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 612.5 58(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,4,6-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 624.5 59(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-isopropylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 612.6 60(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-ethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 598.2 61(S)-2-(tert-butoxy)-2-(5-(2-(3-cyanobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 595.3 62(S)-2-(tert-butoxy)-2-(5-(2-(2-cyanobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 595.3 63(S)-2-(tert-butoxy)-2-(5-(2-(5-cyano-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 613.3 64(S)-2-(tert-butoxy)-2-(5-(2-(4-cyanobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 595.3 65(S)-2-(tert-butoxy)-2-(5-(2-(4-cyano-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 609.3 66(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-fluoro-2-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 656.3 67(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 656.3 68(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 656.3 69(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 656.3 70(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 656.3 71(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 602.3 72(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2,3-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 616.2 73(S)-2-(tert-butoxy)-2-(5-(2-(2,3-difluoro-4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 620.1 74(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-5-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 602.3 75(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3,5-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 616.3 76(S)-2-(tert-butoxy)-2-(5-(2-(3,4-difluoro-5-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 620.3 77(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-isopropylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 612.4 78(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,4,5-trimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 612.2 79(S)-2-(tert-butoxy)-2-(5-(2-(3,5-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 598.3 80(S)-2-(tert-butoxy)-2-(5-(2-(2,3-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 598.3 81(S)-2-(tert-butoxy)-2-(5-(2-(3-(tert-butyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 626.4 82(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 602.3 83(S)-2-(tert-butoxy)-2-(5-(2-(2,5-difluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 636.2 84(S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 636.2 85(S)-2-(5-(2-(2-(benzyloxy)-3,5-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetic acid

Method C: LCMS (M + H) = 744.4 86(S)-2-(tert-butoxy)-2-(5-(2-(4,5-difluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 636.2 87(S)-2-(tert-butoxy)-2-(5-(2-(2,3-difluoro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A, C: LCMS (M + H) = 636.2 88(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-(2-hydroxyethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 630.2 89(S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluoro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 636.2 90(S)-2-(tert-butoxy)-2-(5-(2-(2,4-dichloro-6-ethoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 682.1 91(S)-2-(tert-butoxy)-2-(5-(2-(2,3-dichloro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 668.1 92(S)-2-(tert-butoxy)-2-(5-(2-(2,6-difluoro-3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 636.3 93(S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-2-fluoro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 652.3 94(S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluoro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A, C: LCMS (M + H) = 636.3 95(S)-2-(tert-butoxy)-2-(5-(2-(3,5-difluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A, C: LCMS (M + H) = 636.5 96(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2,3,5-trifluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 624.3 97(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A, : LCMS (M + H) = 618.2 98(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-methoxy-3-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 668.7 99(S)-2-(tert-butoxy)-2-(5-(2-(5-chloro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 634.4 100(S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 634.5 101(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 618.5 102(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 654.1 103(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-ethoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 614.3 104(S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 688.1 105(S)-2-(tert-butoxy)-2-(5-(2-(4-(difluoromethoxy)-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 654.2 106(S)-2-(tert-butoxy)-2-(5-(2-(2,6-(difluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 636.7 107(S)-2-(tert-butoxy)-2-(5-(2-(2,4-(difluoro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 636.7 108(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-4-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpiperidin-3-yl)acetic acid

Method A: LCMS (M + H) = 672.2 109(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-methoxy-4-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpiperidin-3-yl)acetic acid

Method A: LCMS (M + H) = 668.2 110(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A, C: LCMS (M + H) = 654.4 111(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-5-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 672.2 112(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-methoxy-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 668.2 113(S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-5-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 688.3 114(S)-2-(tert-butoxy)-2-(5-(2-(2-(difluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 636.4 115(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.2 116(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.2 117(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: ¹H NMR (500 MHz, DMSO-d₆) δ 7.37 (t, J = 7.7 Hz, 1H),7.15-7.01 (m, 2H), 6.94-6.83 (m, 2H), 6.75 (t, J = 8.3 Hz, 1H), 5.75 (d,J = 9.5 Hz, 1H), 3.84-3.77 (m, 3H), 3.62 (br. s., 1H), 2.91-2.62 (m,8H), 2.42 (s, 3H), 2.11-2.03 (m, 3H), 1.89 (s, 8H), 1.10 (s, 9H), 0.84(br. s., 3H), 0.61 (br. s., 3H). LCMS (M + H) = 618.2 118(S)-2-(tert-butoxy)-2-(5-(2-(3-(difluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 636.2 119(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-methoxy-5-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 614.4 120(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-fluoro-3-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 672.2 121(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(3-(1,1,2,2-tetrafluoroethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 686.2 122(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-5-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.2 123(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(2-(trifluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 654.3 124(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-fluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 618.4 125(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-(1,1,2,2-tetrafluoroethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 686.2 126(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-ethoxy-2,4-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 650.4 127(S)-2-(tert-butoxy)-2-(5-(2-(3,4-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 638.1 128(S)-2-(tert-butoxy)-2-(5-(2-(2,6-dichlorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 638.1 129(S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 634.2 130(S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-2-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 622.1 131(S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.1 132(S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.1 133(S)-2-(tert-butoxy)-2-(5-(2-(5-chloro-2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.1 134(S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.1 135(S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-2,6-difluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 640.1 136(S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-6-fluorobenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 622.1 137(S)-2-(tert-butoxy)-2-(5-(2-(3-chloro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 634.1 138(S)-2-(tert-butoxy)-2-(5-(2-(4-chloro-3-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 634.1 139(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(5-isopropyl-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 642.2 140(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-methoxy-4-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 614.2 141(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-methoxy-3-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 614.2 142(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-fluoro-2-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.3 143(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-isopropyl-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 642.4 144(S)-2-(tert-butoxy)-2-(5-(2-(2,4-difluoro-6-hydroxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 622.3 145(S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 634.5 146(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-4-methoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 618.5 147(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-methoxy-2,3-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 628.2 148(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-methoxy-2,5-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 628.4 149(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-ethoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 614.1 150(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-isopropoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 628.2 151(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-methoxy-5-(trifluoromethyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 668.3 152(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-isopropoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 628.4 153(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-isobutoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 642.4 154(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(3-isopropoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 628.4 155(S)-2-(tert-butoxy)-2-(5-(2-(chroman-6-ylmethyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 626.2 156(S)-2-(tert-butoxy)-2-(5-(2-((2,3-dihydrobenzo[b][1,4]dioxin-6-yl)methyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 628.2 157(S)-2-(5-(2-(3,4-bis(difluoromethoxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetic acid

Method C: LCMS (M + H) = 702.1 158(S)-2-(tert-butoxy)-2-(5-(2-((2,3-dihydrobenzo[b][1,4]dioxin-5-yl)methyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 628.2 159(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(2-fluoro-6-phenoxybenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 680.2 160(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-5-(2-(4-isopropoxy-2,6-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 656.2 161(S)-2-(tert-butoxy)-2-(5-(2-(3,4-dimethylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method A: LCMS (M + H) = 598.4 162(S)-2-(tert-butoxy)-2-(5-(2-(4-(1-cyanocyclopropyl)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 635.2 163(S)-2-(tert-butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethyl-5-(2-(4-(nonyloxy)benzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)acetic acid

Method C: LCMS (M + H) = 712.3

(S)-3-Bromo-5-(1-(tert-butoxy)-2-isopropoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridine1-oxide

To a stirred solution of (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate(16 g, 34 mmol) in DCM (170 ml) was added mCPBA (77% max) (11.7 g, 51.1mmol) at rt over 5 min. After 4 h, the reaction mixture was washed withsat aq Na₂CO₃ (3×50 mL), dried (Na₂SO₄), filtered and concentrated togive(S)-3-bromo-5-(1-(tert-butoxy)-2-isopropoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridine1-oxide (14.6 g, 30.1 mmol, 88% yield). ¹H NMR (500 MHz, chloroform-d) δ6.28 (br. s., 1H), 5.03 (spt, J=6.3 Hz, 1H), 4.00 (t, J=11.4 Hz, 1H),3.50 (td, J=12.1, 2.4 Hz, 1H), 2.91-2.79 (m, 1H), 2.76 (s, 3H),2.67-2.60 (m, 1H), 2.56 (s, 3H), 1.60 (br s, 1H), 1.45 (d, J=12.1 Hz,1H), 1.38-1.31 (m, 1H), 1.22-1.17 (m, 13H), 1.14 (d, J=6.1 Hz, 3H),1.10-1.05 (m, 3H), 1.04-1.00 (m, 3H). LCMS (M+)=485.10, 487.10.

Isopropyl(S)-2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-6-(hydroxymethyl)-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate

To a stirred solution of(S)-3-bromo-5-(1-(tert-butoxy)-2-isopropoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-2,6-dimethylpyridine1-oxide (12.8 g, 26.4 mmol) in anhydrous DCM (132 ml) was added,dropwise, trifluoroacetic anhydride (7.45 ml, 52.7 mmol) over 5 min atrt. After 2 h, sat NaHCO₃(50 mL) was slowly added, stirred for 10 min,aq layer separated, organic layer dried (Na₂SO₄), filtered,concentrated, adsorbed onto Celite and was purified on silica gel(Biotage, EtOAc/hexanes gradient). The major peak was collected toafford (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-6-(hydroxymethyl)-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate(9.7 g, 20 mmol, 76% yield). ¹H NMR (500 MHz, chloroform-d) δ 6.24 (brs, 1H), 5.04 (spt, J=6.3 Hz, 1H), 4.75 (br s, 1H), 4.72-4.59 (m, 2H),4.05 (br s, 1H), 3.48 (t, J=11.0 Hz, 1H), 2.91 (d, J=11.5 Hz, 1H),2.68-2.62 (m, 1H), 2.60 (s, 3H), 1.63-1.57 (m, 2H), 1.45 (d, J=15.0 Hz,1H), 1.39-1.32 (m, 1H), 1.22-1.19 (m, 12H), 1.15-1.12 (m, 3H), 1.08 (s,3H), 1.03 (s, 3H). LCMS (M+H)=485.17, 487.17.

Isopropyl(S)-2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-6-formyl-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate

To a stirred solution of (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-6-(hydroxymethyl)-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate(1.0 g, 2.1 mmol) in CH₂Cl₂ (19 ml) was added Dess-Martin periodinane(1.3 g, 3.1 mmol) at once at rt. After 16 h, the reaction mixture wasdiluted with ether, washed with 1M NaOH followed by brine. The organicphase was dried over (Na₂SO₄), concentrated and purified on silica gel(Biotage, EtOAc/hexanes gradient, 0-100% over 10 CVs) to afford(S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-6-formyl-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate(960 mg, 1.99 mmol, 96% yield). ¹H NMR (500 MHz, chloroform-d) δ 10.29(s, 1H), 6.26 (br s, 1H), 5.12-4.97 (m, 1H), 4.15-4.05 (m, 1H), 3.54 (t,J=12.1 Hz, 1H), 2.94 (d, J=10.9 Hz, 1H), 2.71 (d, J=11.0 Hz, 1H),2.66-2.62 (m, 3H), 1.59 (br s, 1H), 1.51 (br s, 1H), 1.41-1.35 (m, 1H),1.30-1.25 (m, 1H), 1.22-1.18 (m, 12H), 1.16-1.13 (m, 3H), 1.11-1.03 (m,6H). LCMS (M+H)=483.0, 485.0.

(S)-3-Bromo-5-(1-(tert-butoxy)-2-isopropoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-6-methylpicolinicacid

To a solution of (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-6-formyl-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate(2.0 g, 4.1 mmol) in DMSO (41 ml) was added potassium phosphatemonobasic (1.69 g, 12.4 mmol) in water (10 mL) followed by sodiumchlorite (1.12 g, 12.4 mmol) in water (10 mL) and the mixture wasstirred overnight. A ppt formed immediately. As the reaction stirred,the precipitated material stuck to the sides of the flask. Afterstirring overnight, the solution was poured away and the solids weretaken up in EtOAc and were then washed with brine, dried (Na₂SO₄),filtered and concentrated to afford the expected product. The DMSOsolution also contained some product. It was diluted with EtOAc andwashed with Brine. The organic phase was dried over Na₂SO₄, andconcentrated and was combined with the material isolated from the ppt.The combined material afforded a quantitative amount of(S)-3-bromo-5-(1-(tert-butoxy)-2-isopropoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-6-methylpicolinicacid (quantitative). LCMS (M+H)=499.04.

Isopropyl(S)-2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate

Water (0.16 ml, 8.8 mmol) followed by diphenylphosphoryl azide (0.76 ml,3.5 mmol) was added to a stirring solution of(S)-3-bromo-5-(1-(tert-butoxy)-2-isopropoxy-2-oxoethyl)-4-(4,4-dimethylpiperidin-1-yl)-6-methylpicolinicacid (882 mg, 1.77 mmol) in Toluene (18 ml) at rt. The reaction wasstirred at 90° C. for 2 h. The mixture was then diluted with EtOAc andwashed with sat aq NaHCO₃. The organic phase was dried over Na₂SO₄,filtered and concentrated. The reaction was concentrated, adsorbed ontoCelite and purified on silica gel (Biotage, EtOAc/hexanes gradient,0-100% over 10 CVs) to give the expected product (S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2-methylpyridin-3-yl)-2-(tert-butoxy)acetatein quantitative isolated yield. LCMS (M+H)=455.20, 457.20.

Example 164

(S)-2-(tert-Butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(4,4-dimethylpiperidin-1-yl)-2-methylpyridin-3-yl)aceticacid

(S)-Isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate(25 mg, 0.055 mmol),2-(2-chloro-6-methylbenzyl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4-tetrahydroisoquinoline(33 mg, 0.082 mmol), 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl(4.5 mg, 11 μmol), PdOAc₂ (1.2 mg, 5.5 mol) and potassium phosphatetribasic (87 mg, 0.41 mmol) were combined under N₂. 1,4-Dioxane (1 ml)and Water (0.2 ml) were added under N₂. The reaction was heated at 80°C. for 1 h. The reaction was concentrated, adsorbed onto celite and waspurified on silica gel (Biotage, EtOAc/hexanes gradient, 0-100% over 10CVs) The isolated residue was subjected to hydrolysis conditions bytreating with 0.1 mL of 5N NaOH, in 1.5 mL of EtOH, and was stirred at80 C overnight. The reaction mixture containing the product wassubmitted to the Single Compound Purification team for purification andanalysis. The crude material was purified via preparative LC/MS to givedesired product (7.6 mg). ¹H NMR (500 MHz, DMSO-d₆) δ 8.01 (s, 1H), 7.29(d, J=7.3 Hz, 1H), 7.20 (d, J=9.5 Hz, 2H), 7.14-7.08 (m, 1H), 7.06-6.99(m, 2H), 5.81 (s, 1H), 3.83 (s, 2H), 3.69 (s, 2H), 2.80 (dd, J=14.1, 4.2Hz, 4H), 2.49 (br. s., 3H), 2.45 (s, 3H), 1.30 (br. s., 3H), 1.25 (s,3H), 1.12 (s, 10H), 0.88-0.75 (m, 7H). LCMS (M+H)=604.18.

Example 165

(S)-2-(tert-Butoxy)-2-(4-(4,4-dimethylpiperidin-1-yl)-2-methyl-5-(2-(2-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)pyridin-3-yl)aceticacid

(S)-isopropyl2-(5-bromo-4-(4,4-dimethylpiperidin-1-yl)-2-methylpyridin-3-yl)-2-(tert-butoxy)acetate(50 mg, 0.11 mmol),2-(2-chloro-6-methylbenzyl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4-tetrahydroisoquinoline(66 mg, 0.17 mmol), 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl(9.01 mg, 0.022 mmol), potassium phosphate tribasic (175 mg, 0.823mmol), PdOAc₂ (2.5 mg, 11 μmol) were combined under N₂. 1,4-Dioxane (1.8ml) and Water (0.4 ml) was added under N₂. The reaction was stirred at80° C. for 1 hr. The reaction was concentrated, adsorbed onto celite andwas purified on silica gel (Biotage, EtOAc/hexanes gradient 0-100% over10 CVs). The isolated material was taken up in 1.5 mL of EtOH andtreated with 5N aq NaOH (0.20 ml, 1.1 mmol). The reaction was stirredovernight at 80 C. The reaction was purified by preparative reversephase HPLC on a C18 column using a suitably buffered H₂O/CH₃CN gradient.One of the minor peaks with a M+H matching that of titled compound wasre-purified via preparative LC/MS to give desired product (7.1 mg). ¹HNMR (500 MHz, DMSO-d₆) δ 8.02 (s, 1H), 7.36-7.32 (m, 1H), 7.30 (d, J=5.5Hz, 2H), 7.18 (s, 2H), 7.13-7.08 (m, 1H), 7.04 (br. s., 1H), 5.80 (br.s., 1H), 3.64-3.59 (m, 2H), 2.84 (br. s., 1H), 2.74-2.67 (m, 1H), 2.46(s, 3H), 2.38-2.32 (m, 3H), 1.90 (s, 2H), 1.55 (br. s., 3H), 1.29 (br.s., 3H), 1.10 (s, 13H), 0.87 (br. s., 3H), 0.73 (br. s., 3H). LCMS(M+H)=570.25.

Isopropyl2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetate

To a stirred solution of isopropyl2-(5-bromo-4-chloro-2,6-dimethylpyridin-3-yl)-2-oxoacetate (0.8 g, 2.391mmol) and DIPEA (0.501 ml, 2.87 mmol) in anhydrous CH₃CN (2.4 mL) wasadded 3,3-dimethylpiperidine (0.325 g, 2.87 mmol) and the resultingsolution was placed in a pre-heated heating block at 90° C. overnight.The reaction mixture was combined with diluted with ethyl acetate (80mL), washed with water (50 mL), brine (50 mL), dried (MgSO₄), filtered,and concentrated. The residue was purified on ISCO 80 g cartridge (0-25%EtOAC/Hex) to give an isopropyl2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetateas a bright yellow viscous oil (0.74 g, 75%). LCMS (M+H)=413.0.

(S)-Isopropyl2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate

To a solution of isopropyl2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-oxoacetate(0.92 g, 2.237 mmol) and(R)-1-methyl-3,3-diphenylhexahydropyrrolo[1,2-c][1,3,2]oxazaborole(0.447 ml, 0.447 mmol) in Toluene at −50° C. was added catecholborane(0.718 ml, 3.35 mmol) slowly. The reaction mixture was slowly warmed upto −15° C. over 5 h and stirred at −10° C. overnight in a chiller. Thereaction mixture was diluted with ethyl acetate and washed with 1MNa₂CO₃ (50 mL). The organic layer was isolated, washed with 1M Na₂CO₃,dried over Na₂SO₄ and concentrated. The residue was purified on silica(120 g isco column) using 10-50% ethyl acetate in hexanes. The desiredfractions were concentrated to give isopropyl(S)-2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetateas a yellow viscous oil (0.81 g, 1.95 mmol, 87% yield). LCMS(M+H)=415.2.

(S)-Isopropyl2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate

In a 100 ml round bottom flask fitted with a shlenk adaptor with rubberseptum (with empty balloon attached), Isobutylene gas was vigorouslybubbled for 20 minutes into a cooled (0° C.) solution of (S)-isopropyl2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-hydroxyacetate(0.81 g, 1.960 mmol) and perchloric acid (0.168 ml, 1.960 mmol) in DCM(39 mL) until the volume doubled and the balloon filled to firmness.After 2 hrs, the isobutylene line was disconnected and needle pulled tojust above the solution line then connected to a bubbler to monitorisobutylene gas exit. The reaction mixture was stirred at 0° C. for 1 h,the ice bath was removed and warmed up to rt while monitoring forconversion. After 2 hrs the reaction appeared to go to full conversionaccording to LCMS. The reaction mixture was poured into a 500 mLErlenmeyer flask and made basic with 2M sodium carbonate whilevigorously stirring. The organic layer was separated and washed withwater, followed by brine, collected, dried (MgSO₄), filtered andvolatiles evaporated to give a yellow oil as the crude product. Thecrude product was purified on silica gel (80 g column, 10-50% EtOAc/Hex)to give the product (S)-isopropyl2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate(0.704 g, 1.50 mmol, 77% yield) as a yellow viscous oil. ¹H NMR (500MHz, CDCl₃) δ 6.40 (br. s., 1H), 5.14-4.97 (m, 1H), 3.89 (t, J=10.3 Hz,1H), 3.24 (d, J=11.2 Hz, 1H), 2.91-2.40 (m, 9H), 1.85 (d, J=11.7 Hz,1H), 1.68 (d, J=11.5 Hz, 1H), 1.51 (d, J=12.9 Hz, 1H), 1.42-0.86 (m,22H). LCMS (M+H)=470.1.

(S)-Isopropyl 2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-,2,3,4-tetrahydroisoquinolin-6-yl)-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetate

A mixture of (S)-isopropyl2-(5-bromo-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)-2-(tert-butoxy)acetate(0.07 g, 0.149 mmol),2-(2-chloro-6-methylbenzyl)-6-(4,4,5,5-tetramethyl-1,3,2-dioxaborolan-2-yl)-1,2,3,4-tetrahydroisoquinoline(0.089 g, 0.224 mmol), 2-dicyclohexylphosphino-2′,6′-dimethoxybiphenyl(0.012 g, 0.030 mmol), palladium(II) acetate (3.35 mg, 0.015 mmol) and2M K₃PO₄ (0.559 mL, 1.118 mmol) in 1,4-dioxane (1772 μl) under N₂. Thereaction mixture was degassed for 5 min and heated at 80° C. for 1 h.The organic layer was isolated and purified on silica gel (24 g, iscocolumn) using 0-85% ethyl acetate in hexanes. The desired fractions wereconcentrated to give (S)-isopropyl2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetateas a light brown foamy solid (57 mg, 0.086 mmol, 58%). LCMS (M+H)=661.5.

Example 166

(S)-2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)aceticacid

NaOH (0.173 mL, 0.863 mmol) was added to a solution of (S)-isopropyl2-(tert-butoxy)-2-(5-(2-(2-chloro-6-methylbenzyl)-1,2,3,4-tetrahydroisoquinolin-6-yl)-4-(3,3-dimethylpiperidin-1-yl)-2,6-dimethylpyridin-3-yl)acetate(0.057 g, 0.086 mmol) in ethanol (1.5 mL) and the mixture was heated at80° C. for 4 h. Additional NaOH (0.173 mL, 0.863 mmol) was added and themixture was heated for 6 h, cooled purified by preparative LC/MS to givedesired product (32.0 mg, 0.052 mmol, 60%). LCMS (M+H)=619.3.

Biological Methods

Inhibition of HIV Replication:

A recombinant NL-RLuc proviral clone was constructed in which a sectionof the nef gene from NL4-3 was replaced with the Renilla Luciferasegene. This virus is fully infectious and can undergo multiple cycles ofreplication in cell culture. In addition, the luciferous reporterprovides a simple and easy method for quantitating the extent of virusgrowth and consequently, the antiviral activity of test compounds. Theplasmid pNLRLuc contains the proviral NL-Rluc DNA cloned into pUC18 atthe PvuII site. The NL-RLuc virus was prepared by transfection of 293Tcells with the plasmid pNLRLuc. Transfections were performed using theLipofectAMINE PLUS kit from Invitrogen (Carlsbad, Calif.) according tothe manufacturer and the virus generated was titered in MT-2 cells. Forsusceptibility analyses, the titrated virus was used to infect MT-2cells in the presence of compound, and after 5 days of incubation, cellswere processed and quantitated for virus growth by the amount ofexpressed luciferase. Assay media was RPMI 1640 supplemented with 10%heat inactivated fetal bovine serum (FBS), 100 units/ml penicillin G/100units/ml streptomycin, 10 mM HEPES buffer pH 7.55 and 2 mM L-glutamine.The results from at least 2 experiments were used to calculate the EC₅₀values. Luciferase was quantitated using the Dual Luciferase kit fromPromega (Madison, Wis.). Susceptibility of viruses to compounds wasdetermined by incubation in the presence of serial dilutions of thecompound. The 50% effective concentration (EC₅₀) was calculated by usingthe exponential form of the median effect equation where(Fa)=1/[1+(ED₅₀/drug conc.)^(m)](Johnson V A, Byington R T. InfectivityAssay. In Techniques in HIV Research. ed. Aldovini A, Walker B D. 71-76.New York: Stockton Press. 1990). Results are shown in Table 1. Activityequal to A refers to a compound having an EC₅₀≤100 nM, while B and Cdenote compounds having an EC₅₀ between 100 nM and 1 uM (B) or >1 uM(C).

TABLE 1 Compound Activity EC₅₀ μM Compound Activity EC₅₀ μM  1 A 0.006 84 A  2 A  85 A  3 A  86 A  4 A  87 A  5 A  88 A 0.012  6 A  89 A  7 A0.004  90 A  8 A  91 A  9 A  92 A 10 C 1.475  93 A 11 A  94 A 12 A  95 A13 A  96 A 0.003 14 A 0.034  97 A 15 A  98 A 16 A  99 A 17 A 100 A 18 A101 A 19 A 102 A 20 A 103 A 0.012 21 A 104 A 22 A 105 A 23 A 0.003 106 A24 A 107 A 25 A 108 A 26 A 109 A 27 A 110 A 0.008 28 A 111 A 29 A 112 A30 A 113 A 31 A 0.011 114 A 32 A 115 A 33 A 116 A 0.002 34 A 117 A 35 A118 A 36 A 119 A 37 A 120 A 38 A 0.006 121 A 39 A 122 A 40 A 123 A 0.01141 A 124 A 42 A 125 A 43 A 126 A 44 A 127 A 45 A 0.003 128 A 46 A 129 A0.003 47 A 130 A 48 A 131 A 49 A 132 A 50 A 133 A 51 A 0.003 134 A 0.01252 A 135 A 53 A 136 A 54 A 137 A 55 A 138 A 56 A 139 A 0.03 57 A 140 A58 A 141 A 59 A 0.058 142 A 60 A 143 A 61 A 144 A 0.008 62 A 145 A 63 A146 A 64 A 147 A 65 A 148 A 66 A 0.013 149 A 67 A 150 A 0.021 68 A 151 A69 A 152 A 70 A 153 A 71 A 154 A 72 A 155 A 73 A 0.007 156 A 0.008 74 A157 A 75 A 158 A 76 A 159 A 77 A 160 A 78 A 161 A 79 A 162 A 80 A 0.003163 A 0.076 81 A 164 A 0.003 82 A 165 A 83 A 166 A 0.023

It will be evident to one skilled in the art that the present disclosureis not limited to the foregoing illustrative examples, and that it canbe embodied in other specific forms without departing from the essentialattributes thereof. It is therefore desired that the examples beconsidered in all respects as illustrative and not restrictive,reference being made to the appended claims, rather than to theforegoing examples, and all changes which come within the meaning andrange of equivalency of the claims are therefore intended to be embracedtherein.

We claim:
 1. A compound of Formula I

or a pharmaceutically acceptable salt thereof wherein: R¹ is hydrogen,C₁₋₆alkyl, or C₃₋₇cycloalkyl; R² is tetrahydroisoquinolinyl and issubstituted with 1 R⁶ substituent and also with 0-3 halo or C₁₋₆alkylsubstituents; R³ is azetidinyl, pyrrolidinyl, piperidinyl, piperazinyl,morpholinyl, homopiperidinyl, homopiperazinyl, or homomorpholinyl, andis substituted with 0-3 substituents selected from cyano, halo,C₁₋₆alkyl, C₁₋₆haloalkyl, C₁₋₆alkoxy, and C₁₋₆haloalkoxy; R⁴ isC₁₋₆alkyl or C₁₋₆haloalkyl; R⁵ is C₁₋₆alkyl; R⁶ is Ar¹, (Ar¹) C₁₋₆alkyl,(chromanyl)C₁₋₆alkyl, cyanoC₃₋₇cycloalkyl or (dihydrobenzodioxinyl)C₁₋₆alkyl; and Ar¹ is phenyl substituted with 0-5 substituents selectedfrom cyano, halo, C₁₋₆alkyl, C₃₋₇cycloalkyl, C₁₋₆haloalkyl, hydroxy,C₁₋₆alkoxy, C₁₋₆haloalkoxy, (hydroxy)C₁₋₆alkoxy-(C₁₋₆alkoxy)C₁₋₆alkoxy,phenoxy, benzyloxy, carboxy, phenyl, and cyanoC₃₋₇cycloalkyl.